Category Archives: Global

At power generating facilities there are fans that require both sound and thermal treatments, and others that only require one treatment or the other. These fans can present problems for sound and thermal control.

Fans produce two different types of noise-tonal and broadband. A tonal noise is generated when the blades pass by a stationary cutoff within the fan. A broadband noise is produced by the flue gas moving through the system. Both noise types are generated inside the fan. The sound travels out of the inlet box opening through the outlet flue of the fan and through the fan casing. All three paths must be considered in noise control. Inlet and outlet sound levels are most commonly controlled by adding absorptive or resonant-type silencers to the fan.

Acoustical insulation and lagging can be applied around the fan to limit the noise radiated from the casing. When noise reduction lagging and insulation is required, the effect of insulation thickness and optimal amount of jacket mass should be considered for the best economic value. Also, it’s always more cost effective to treat the noise at the source.

The following terms are most commonly used when considering fan noise and sound control.

Noise
Noise is simply unwanted sound. For this discussion, sound and noise will mean the same thing. Noise is measured with a sound level meter, which measures the sound pressure level.
Decibel (dB)
A decibel is the common unit of measure of sound. There are several standard weightings used for various reasons. In this case we shall only be concerned with "A-weighting."
A – weighting
A – weighting is the frequency sensitive corrections applied to linear sound level readings to approximate the way humans perceive sound.
Free Field
Free field refers to any wide-open area or space that has nothing around to reflect or interfere with sound in any direction.
Flue
Flue identifies a piece of equipment or component that has boiler exhaust gas passing through it (i.e. flue from the air heater to induced draft fan).
Duct
Duct identifies a piece of equipment or component that has air passing through it (i.e. duct from the forced draft fan to steam coil air heater).
Fan
A fan is a piece of equipment that consists of a bladed rotor or impeller, located in a housing, and designed to collect and redirect the air or gas by adding sufficient energy to the medium to initiate motion and overcome resistance to the flow.
Forced Draft Fans (FD Fans)
Forced draft fans are located before the air heater inlet. They move air temperatures ranging from ambient to 200 degrees Fahrenheit (F), depending on where the steam coil air heater is located (before or after the FD fan). Most often, the FD fan is located before the steam coil air pre-heater and will not require any thermal insulation for personnel protection, but may require acoustical sound and noise protection.
Induced Draft Fans (ID Fans)
Induced draft fans (ID fan) are located at or near the stack, and normally move gas temperatures ranging from 350 degrees F to 150 degrees F. Steam-generating boilers designed to operate with a balanced furnace draft or without a forced draft fan require an ID fan. An ID fan will draw the flue gas out of the boiler through the air heater and air pollution equipment and then exiting up through the stack. The operating temperatures of the ID fans will require thermal insulation for personnel protection and may also require acoustical sound and noise protection.
Gas Re-circulating Fans (GR Fans)
Gas re-circulating fans (GR fans) are used for controlling steam temperature, furnace heat absorption and slagging of heating surfaces. GR fans are located in a flue system that is re-circulating or sending gas back to the furnace for reheating. Gas from the boiler, economizer or air heater outlet is re-introduced to the furnace by the GR fans. The flue gas temperature that the fan is re-circulating back to the furnace is between 500 degrees and 700 degrees F, depending on where the flue gas is taken. In most instances, the flue gas is obtained from the economizer outlet flue. The operating temperatures of the GR fans will require thermal insulation for heat conservation, and may also require acoustical sound and noise protection.
Primary Air fans (PA fans)
Primary air fans (PA fans) are used for controlling airflow into a pulverizer (used to grind coal). The air amount and velocity will help in the combustion of fuel for the steam-generating boiler. The air drawn from the air heater is usually in a temperature range between 400 degrees and 700 degrees F, depending upon the size of the boiler. The operating temperatures of the PA fans will require thermal insulation for heat conservation and may also require acoustical sound and noise protection.
Secondary Air Fans (SA Fans)
Secondary air fans (SA fans) are used for controlling airflow into a windbox (a large vestibule that houses the burners). The air amount and the air velocity will aid in the fuel combustion for a steam-generating boiler. The air drawn from the air heater is usually in a temperature range between 400 degrees and 700 degrees F, depending upon the size of the boiler. The operating temperatures of the SA fans will require thermal insulation for heat conservation and may also require acoustical sound and noise protection.
Thermal and Acoustics

There are many ways to insulate and lag a fan. Most thermal insulation applications provide some type of acoustical benefit. However, the attachment method and the thermal insulation system location are critical for sound protection.

For example, if dealing with noise that’s radiating from the vibrating surface of the fan, installing a layer of rigid insulation material tightly against a fan housing would only create a larger vibrating surface and produce higher noise levels. Therefore, avoid a thermal and acoustical insulation system that uses a rigid attachment. The most logical method, in this case, would be to build a thermal/acoustical wall system around the fan. This system would be able to absorb some of the sound on the fan side, but not vibrate along with the fan. This can be done using a freestanding wall system or a system using isolators that would act as springs or shock absorbers. Either method requires space around the fan and can become expensive to install. The norm is to install a wall system of prefabricated panels secured to a frame that’s attached to the fan at a minimum number of well-chosen places.

To design an insulation/acoustic system, follow these steps:

  • Inspect the fan and its surroundings before selecting treatment methods to reduce the fan noise. Other nearby noise sources will affect your design.
  • Take into account the amount of room around the fan and its surrounding noise levels. This will determine the attachment method.
  • Remember that regardless of how much you reduce the noise from a fan, the surrounding area can’t be quieter than the combined noise from the other sources.
Sound Levels

The Occupational Safety and Health Administration (OSHA) has set certain standards to protect workers exposed to noise levels. OSHA Standards number 1910.95 for noise exposure states that the employer shall administer a continuing effective hearing conservation program when employees are exposed to an average sound level of 85 decibels or more in an eight-hour day. In the steam and power generating industry, this usually means requiring earplugs and adding acoustical sound protection to their equipment (such as fans).

The chart that follows represents the A-weighted sound levels and the duration a person can be exposed to that level of sound per day. However this A-weighted chart is based on measurement by a dosimeter or a sound meter.

Duration Per Day Sound Level
8 hours 90 decibels
6 hours 92 decibels
4 hours 95 decibels
3 hours 97 decibels
2 hours 100 decibels
1-1/2 hours 102 decibels
1 hour 105 decibels
1/2 hour 110 decibels
1/4 hour or less 115 decibels

OSHA amended or adjusted the preceding values for the human ear, known as a Time Weighted Average (TWA) and set 50 percent as the equivalent value. The formula OSHA used to set this new value was TWA=16.61 log (10) (D/100) + 90, where D represents the accumulated dose in percent exposure. This means that OSHA, to protect the employee, has set a TWA value of 85dB (not the A-weighted value of 90dB) as the maximum permissible sound level for an 8-hour exposure period.

Acoustical System Materials

Lagging is a common element in most acoustical surface treatments. The lagging material is usually aluminum or galvanized steel. Galvanized steel lagging is often better than aluminum lagging because steel has a heavier surface mass. The particulars of the noise problem may dictate what type of lagging will be used. For example, if the noise is a low frequency problem (a rumble type noise) then a lagging with more mass like galvanized steel is desirable. If the noise is mostly at high frequencies (a hissing noise) then a lighter material like aluminum lagging may be used. There are many other considerations, such as stiffness, ring frequency, transmission loss versus frequency, and other conditions that should be considered.

Insulation used as the absorptive filler in acoustical systems can vary, but it’s common to use basalt or mineral wool type insulation. Fiberglass is more popular at ambient temperatures and a better sound absorber. Ceramic fiber is used extensively in combustion turbine exhaust systems where temperatures often exceed 1,000 degrees F. It’s important to choose the right insulation material to fit the conditions of service.

Septum lining barriers are sometimes used between the absorptive layers of insulation in surface treatments to improve the sound transmission loss across a composite wall. Septum linings are usually made of a limp mass such as a mass loaded rubber or vinyl material. Perforated metal facings are frequently used to protect the insulation from erosion. The perforated facing will allow noise to pass through to be absorbed by the insulation.

A Typical Fan Problem

Here’s an example of a typical fan problem. A company orders two new forced draft centrifugal fans and two new motors from different vendors. Being safety conscious, the company specifies both the motors and the fans, when measured at a distance of 3 feet away, can’t have noise levels in excess of 85 dB. The fans and motors are tested at their respective factories and are confirmed to operate at 85 dB as specified.

Upon arrival at the site, the fans and motors are installed close together in an out-of-the-way spot of a corner formed by two painted, masonry block building walls. Immediately upon startup, it’s apparent that the fans and motors together are very noisy. A noise measurement confirms a level of 96 dB near the fans.

The next step is to look at the problem. Here are two fans and two motors each capable of producing a noise level of 85 dB in a free field. Remembering that decibels are logarithmic terms, we have to add all four logarithmic values together of all the equipment that’s located in the same free field. We find that four 85’s add up to 91 dB. Next, the review of the location of the fans and motors show they’re located between two building walls that form a corner. Sound reflecting back from walls forming a corner can amount to as much as 5 dB. This then accounts for the measurement of 96 dB.

The available means to mitigate the noise are:

Acoustical Covering
Acoustical coverings are necessary for any successful solution.
Motor Silencers
Motor silencers can be purchased from several companies who specialize in this form of noise control and can be custom designed. A motor silencer typically consists of an acoustically lined shroud around the motor casing, with an absorptive silencer directing cooling air to the motor fan. The biggest problem to look for when adding a motor silencer is the potential for overheating the motors.
Absorptive Material on the Building Walls
Absorptive material on the building walls can optionally help by reducing the amount of necessary treatment. Adding absorption materials on building walls can achieve fairly low cost results depending on the aesthetic requirements. This can be as simple as adding absorptive blankets consisting of fabric-covered absorptive insulation material placed on portions of the reflective surface.
In-line Silencers
In many cases, In-line silencers are a viable option if the fan ductwork is extensive and there’s no requirement for thermal insulation. Adding in-line-silencers in the ducts near the fans can replace extensive areas of surface treatment.

The cost of reducing the motor noise with motor silencers, compared to the cost of reducing casing/duct radiated noise by acoustical coverings, is estimated to be about the same per dB. Therefore, it would be logical to reduce both by the same amount. For this example, we shall opt not to use any absorptive treatment on the building walls. We must take into account the 5 dB of the untreated surrounding building walls. This means the sum of our four treated noise sources (two fans and two motors) must now be 80 dBA (85 dBA minus the surrounding build-up noise of 5 dB). To achieve the 80 dB, we have to add all four logarithmic values together. When we do that, we find that four 74’s add up to 80 dB.

Our next step is to take our original combined sound level value for the fans and motors of 91 dB and subtract the revised combined sound level value of 80 dB. This leaves 11 dB of noise that must be accounted. This 11 dB will require only nominal motor silencers and acoustical lagging treatment being added. In our example, the ductwork of the fans required no thermal insulation, were fairly extensive in length, and their noise contained only a noticeable amount of tonal noise. Therefore, it was decided to install a tuned-dissipative in-line silencer in the duct fairly near the fan. Finally, we extended the acoustical covering of the casing and ducts to the middle or end of the silencer (away from the fan).

Since there is ample room around the equipment, the acoustical covering can be achieved by either of following methods:

Example 1

Against the fan housing – A support system could be installed to support the acoustical insulation and lagging system. This may be done by a built-out angle support and sub-girt system or by utilizing the existing fan stiffeners to achieve the appropriate air space and wind loading requirements. Then a *pre-insulated lagging panel system or a **conventionally built-up insulation and lagging system can be installed.

*A pre-insulated lagging panel system is a lagging and insulation system that consists of a shop-or-field fabricated lagging sheet lined on the backside with insulation. The lagging is laid face down on a table in the shop. The insulation pins are welded to the lagging sheet on approximately 12 inch centers. The insulation material is impaled over the pins in double layer application with a septum lining between each layer. Aluminum foil is placed over the insulation and will reflect some of the heat back in and is equivalent to about a 1/2 inch of insulation. A galvanized mesh (generally 2 inches x 2 5/8 inches, 16 gauge) is placed over the foil. The mesh keeps the insulation in place and will prevent the fibers from settling to the bottom or eroding away. A 2-1/2 inch square speed clip is placed on the pins, which are bent over to hold the panel together. This insulated lagging sheet or panel will then attach to the outside of the stiffeners directly or to a sub system made from angle iron.

**A conventionally built-up insulated and lagged system is a lagging and insulation system where each component (insulation and lagging) will be attached separately.

Example 2

Sound enclosure – Acoustic sound panels would be fabricated in the shop or in the field at a location and then attached to a steel structure. This steel structure would be independent of the fans and the sound enclosure would completely enclose the fan.

Enclosures, duct silencers, motor silencers, and sound absorptive panels are only some of the tools needed to effectively control noise. No one product or method works for every situation. However, in most cases, any reduction of noise and creating sound control will benefit all work environments.

Scott Weiss is no stranger to large construction projects. As a vice president at Kamco Building Supply, Weiss has visited many big building sites over the years. Still, he was impressed when he first saw the new Washington Convention Center in Washington, D.C.

"When we first saw the project, it was a tremendous hole in the ground," said Weiss. "The excavation was so large the crane work and construction equipment actually looked like Tonka toys in there."

No wonder. The new Washington Convention Center is the largest public works project in the District since the city was first constructed. It will be the largest building in Washington and is being built in the largest excavation in the Western Hemisphere. To get the space they needed without violating the District’s strict limits on building height, the 17-acre site was carved out to 50 feet below ground level. It covers approximately six city blocks in the downtown business district.

To give you an idea of how much space the structure will enclose, the Sears Tower could comfortably fit inside. In the main exhibit hall, four 747s could sit on two major league baseball fields or six football fields. The new center will use as much steel as seven Eiffel Towers.

Scheduled for completion this spring, the new Washington Convention Center will contain 2.3 million square feet of floor space, attract an estimated 2.5 million visitors, and is expected to bring $1.4 billion in community economic stimulus each year. The new center is almost three times as large as its predecessor, a concrete box of a building just a block away. When that 800,000-square-foot facility opened in 1983, it was the fourth-largest convention center in the United States. But by 1997, a nationwide convention-center boom left the District far behind, dropping its center to No. 30.

In short, the new convention center will be a monumental building worthy of the nation’s capital. Located in a neighborhood with interesting facades, the building will complement the surrounding townhouses with glass, brick, limestone and granite. At night, it will be a big lantern to the city. Grand light-filled spaces will usher visitors to meetings or exhibits.

Topping it all off will be the largest ballroom (52,000 square feet with a dinner seating capacity of 5,000) on the East Coast with a panoramic view of Washington’s impressive monuments. The facility is the culmination of more than 10 years of effort, from a financial feasibility study begun in 1992 to a groundbreaking ceremony in 1998 to the completion of the steel framework in 2001.

Working quietly and efficiently to conserve energy and keep everyone comfortable inside the building will be a variety of insulation products, including extruded foam insulation and a variety of commercial and mineral wool insulation products.

Owens Corning provided much of the insulation products for the building. Advanced Specialty Contractors, Jessup, Md, installed them.

Kevin Sisk, construction superintendent for Advanced Specialty Contractors, said they used more than 25 truckloads of material on the project. "There were about 400 rolls of duct wrap and the rest of it [was] pipe covering."

No stranger to large projects-Sisk also worked on the National Archive in Adelphi, Md., which included 10 buildings in a single endeavor-he admitted that the convention center is special. He said the challenges were the same as any other job, but were magnified by the fact that the convention center is two city blocks wide and six city blocks long.

"It’s just like it is anywhere else these days," says Sisk. "They are all challenging, but in this case the amount of material and the movement of materials is especially challenging. And everything is up in the air; quite high, as a matter of fact. A lot of the work on the job [had to be] done out of lifts; there is very little ladder work on that entire job."

Kamco Supply Corp. supplied the interior package and exterior framing. Weiss said his company supplied more than a million square feet of insulation products, including both fiber glass and mineral wool insulation. Applications include sound attenuation, fire safety and thermal performance.

"It’s an enormous undertaking," said Weiss during the construction process. "It’s going to take quite a bit of manpower to supply. It’s a good job for us. The steel framing and interior metal [totaled] about 3 million lineal feet. The drywall alone is about 6 million square feet.

"We haven’t even scratched the surface yet," he said early in the construction phase of the project. "We’ll be down there every day for at least a year and a half."

A Road Runs Through It

One special feature of the new Washington Convention Center will be an underground plaza goes right through the middle of the building. There will be exhibit and meeting space above the plaza, and a heated work area below. Exhibitors and others will be able to bring tractor-trailers into the center of the building to unload their displays and convention supplies.

Because parts of the plaza will be exposed to the elements and have a heated area under it, contractors poured concrete over foam insulation. Workers first poured a concrete slab floor, then added a hot-fluid-applied waterproofing membrane, topped that with foam insulation, and then poured a topcoat of concrete.

"It’s a roadway that’s also a roof," said Steve Gordon, sales representative for Owens Corning Foamular insulation. "That’s really what it is. They have to insulate the plaza deck because there is heated space under it."

Gordon says the job was originally designed for 60-pound board, but there were concerns about the compressive strength of the material. "We worked with the architect and engineer to change the specification. That was about a four-year project."

As a result, there’s about 400,000 square feet of foam insulation in plaza decks at the new convention center.

The foam insulation offers compressive strength of 100 pounds per square inch. It’s designed for use in high load-bearing applications and is ideal of under slabs, concrete floors and over foundation walls. The superior water resistance of extruded foam insulation also assures stable thermal performance.

Foam insulation is also being used in two other applications, as perimeter insulation around the foundation, and in the wall cavity behind the exterior brick veneer.

Strong Relationships

Large projects always require good working relationships among everyone involved. The new convention center is no exception.

"A job like this is an ongoing project; it’s not just a one-shot deal," said Weiss "There needs to flexibility in schedules, flexibility in delivery times, and there has got to be communication back and forth. We’ve had a long-standing relationship with [Owens Corning]. If there is a problem, we can get together with them and work it out."

The convention center was scheduled for completion by March 2003 with a budget estimate of about $800 million. And with an assist from insulation, convention goers are sure to be comfortable and cozy in the new building.

Thermal insulation provides many uses in industrial (power and petrochemical) and commercial applications. In this story, we will only discuss industrial applications. In simple terms, thermal insulation reduces heat flow from one surface to another. For hot (above ambient) applications, thermal insulation reduces heat loss. On cold (below ambient) applications, the insulation generally serves to minimize heat gain.

In some cases, the application design purpose may seem unrelated to heat loss or heat gain. However the net result is that heat transfer is reduced. Examples of this are insulation for personnel protection and condensation control (sweating). In personnel protection, enough insulation is provided to keep the surface below a given temperature. For condensation control, enough insulation is provided to keep the surface temperature above the dew point. In both cases, insulation is used to control the surface temperature for a desired effect other than thermal conservation. The effect, however, is that in both cases heat transfer is reduced to maintain the surface temperature at a given design criteria.

Correctly designing and specifying an insulation system is much more involved than just selecting a particular material. An insulation system is any combination of insulation materials used in conjunction with mastics, adhesives, sealants, coatings, membranes, barriers, and/or other accessory products to produce an efficient assembly to reduce heat flow. Frequently, the design of insulation systems can either determine or direct the ultimate performance of the process. Improperly designed insulation systems are subject to damage and degradation. Degradation will compromise the material’s performance characteristics, and in many cases the entire process for which the insulation system was designed.

There are many different types of insulation materials available. Each has its own set of properties and performance characteristics. And for each insulation material available, a correct application procedure and corresponding accessory material(s) or "system" application is available. The single most important thing to remember is the word "system." This refers not only to the insulation materials, but also the application and finish.

When asked to supply an insulation specification for a power plant or process plant, several questions must first be considered before design can start. Some examples are:

  • What are the temperature limits of the items to be insulated?
  • Where is the plant geographical location and what are the environmental conditions?
  • What fluids are being insulated?
  • Why is insulation required?
  • What type of insulation material should be used?
  • What type of finish is necessary?
    What Are the Temperature Limits?

What are the temperature limits for insulated items? This starts the entire design and material selection. For a power plant, it’s usually in a range above 32 degrees Fahrenheit (F) to about 1,200 degrees F. At an ethylene plant, the range is between minus 250 degrees F and 1,200 degrees F. This requires two very different types of design considerations, although the materials and application for the 32 degree F range and 1,200 degree F range could be the same. This also necessitates the need for expansion and contraction joints.

The design of hot service insulation expansion joints and insulation supports are quite important. In steam system design (1,000 degrees F) the piping would expand .095 inches per foot of pipe, and the insulation (calcium silicate or perlite) would contract .024 inches per foot. A total of 5.95 inches of expansion must be accounted for if the pipe length was 50 feet. The pipe expansion must still be accounted for, even though some materials will not contract (such as mineral wools). It’s also important to control where the expansion will occur. On vertical piping and equipment, this is done with the use of insulation/expansion supports. Without these, all the expansion will occur at the top.

In cold insulation design, contraction joints are just as important as expansion joints are to hot insulation. If the system has an operating temperature of minus 100 degrees F, the pipe (stainless steel) will contract 0.0176 inch per foot and the insulation, depending on the material, will contract 0.01 inch per foot for cellular glass insulation to 0.102 inch per foot for polyisocyanurate insulation.

Geographic and Environmental Factors

Geographic design considerations depend on plant location. Facilities located in hot and humid climates will have different parameters than those located in a dry, cooler climate. The National Weather Bureau, the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., U.S. meteorological services, sited data or similar service provides local weather data, which can be used in determining the minimum, maximum and average daily temperatures, wind, humidity and rainfall.

Review of the following parameters should give the necessary design data:

  • Wind
  • Snowfall
  • Extreme temperatures
  • Relative humidity
  • Rainfall
  • Water table
  • Seismic readings

It’s important to know if a plant location is near an industrial complex, where potentially corrosive chemicals are present, or near coastal areas, which can affect the selection of insulation and weatherproofing materials along with application procedures. Insulated equipment located near a cooling tower or ash handling equipment will be exposed to a more corrosive environment than will the other plant equipment.

Wind conditions (both positive and negative [back side negative pressure]) must be considered in insulation design. In hot service, the weatherproofing could be supported off of angle irons attached to the vessel or vessel support system. The insulation material could be rigid enough to support the positive pressure of the weatherproofing, but the attachments must be strong enough to resist the negative pressure on the backside. Corrugated metal is usually preferred on vessel sidewalls held in place with stainless steel bands on 18 inch centers and screws in the vertical overlapping seams.

What Fluids Are Being Insulated?

Insulation design for pipe and equipment that handles hazardous chemicals such as flammable or toxic materials requires special consideration in selecting insulation materials, weatherproofing materials and application methods.

Insulation materials that can absorb fluids (such as hot oils/heat transfer fluids) and cause that fluid’s flash point to be reduced shouldn’t be used in such service. Non-absorbent type insulation materials should be used in these services.

Non-absorbent type insulation materials may also be required for toxic services, where trapping of a toxic substance in the insulation can pose health hazards.

Why Is Insulation Required?

Why is insulation required? Because it’s necessary! But the real question is, is it necessary to limit heat loss, for personnel protection, to reduce heat gain, to limit surface condensation, to provide process control or for product stabilization, freeze protection, noise control and fire protection? Each of these may require different thickness, materials, finish and extent of insulation.

Limit Heat Loss or Heat Conservation

Insulation by itself will not maintain or hold temperatures within a system. Insulation can only provide a means to limit, conserve, control, reduce, or minimize the rate of heat flow through a system. But it can’t stop the process. Insulation is merely a heat flow reducer, not a barrier to heat flow.

It might be that condensate and blowdown lines to drains or holding tanks may require insulation to limit heat loss, but heat losses through valves and flanges isn’t critical to the system; therefore they’re not insulated (although personnel protection may be required).

Personnel Protection

When designing insulation systems for personnel protection, only enough insulation shall be used to reduce the surface temperature to an acceptable limit to prevent individuals from getting burned from the surface. Traditionally, the insulation surface’s upper temperature when designing for personnel protection is 140 degrees F. To date, no mandates or statutes govern the upper limit for personnel protection. Refer to "ASTM C1055 – Standard Guide for Heated System Surfaces Conditions That Produce Contact Burn Injuries," for guidance in selecting acceptable temperature limits.

Insulation for personnel protection is generally applied only in those areas accessible to persons during normal plant operation and maintenance, and applied to a high of 7 feet above or 3 feet from platforms or work areas.

In some system designs where there’s no justification for insulation, and the insulation could actually be detrimental to the process, fabrication guards may be employed to provide personnel protection.

When insulation is used for personnel protection, it’s very important to flash the ends to prevent water or moisture from getting behind the insulation, and to prevent insulation deterioration and surface corrosion. Note that most mastics and sealants could have temperature limits lower than the operating or design temperature of the surface receiving the personnel protection.

In situations where solar loads are high, highly reflective metal jacketing materials reflect much of the radiant heat, thereby creating surfaces that could be too hot to touch. Dull, textured, or painted surfaces tend to absorb more of the radiant heat, creating a surface condition cooler to the touch. Gray coated metal jacketing can reduce insulation thickness for personnel protection by as much as 2 inches. As a general rule, the closer the materials emittance is to 1, the cooler the surface temperature will be.

Wind conditions also influence the selection of insulation for personnel protection. For example, in open areas in coastal regions, there’s usually a prevailing wind that can be considered in the insulation design. In this situation, less insulation would be required than in an enclosed space sheltered from the wind.

Reducing Heat Gain on Cold Surfaces

In below ambient applications, the main objective of providing insulation is reducing heat gain and preventing moisture migration or water intake into the system. This type of moisture migration will have a dramatic effect on insulation performance. Cold systems are more subject to degradation from the environment than are hot systems, because of the direction of the vapor driving force. On hot insulation systems, the water vapor’s driving force is away from the hot surface, and although the ingress of water into the insulation can adversely affect performance, it’s generally considered to be temporary. Conversely, on cold systems, the water vapor’s driving force is inward toward the colder surface.

The ingress of water into the insulation will gradually increase with time. The moisture will slowly deteriorate and eventually destroy the system. For this reason, it’s extremely important that the total insulation system design be detailed and well-planned, using vapor barrier mastics, vapor barrier stops and low permeability joint sealants.

Usually, the cost of removing Btu’s (heat gain) by refrigeration is greater than that of producing process Btu’s (heat loss) by heat generating equipment. Therefore, the heat gain in cold processes must be kept to a minimum. The typical rule of thumb is to provide sufficient insulation to maintain an 8-10 Btu·hour/feet2 heat gain to the cold process. The design’s ambient temperature and wind conditions must be utilized when calculating the insulation thickness.

In cold insulation system design, vapor barriers and vapor stops are extremely important. Vapor stops, which seal the insulation to the pipe or equipment, should be installed at all insulation protrusions and terminations. These vapor stops will prevent any failure of the insulation system from traveling along the entire system.

Limiting or Controlling Surface Condensation

Insulation systems can be designed to limit or retard condensation, but in most cases they can’t be designed to "prevent condensation." In humid regions it’s unfeasible to consider designing an insulation system to prevent condensation 100 percent of the time. In these areas, the required thickness of even the most efficient insulation would be unrealistic from both a financial and practical standpoint.

Insulation thickness is determined using ambient conditions and relative humidity, along with the process operating temperature and surface emittance. The insulation system should be designed to keep the surface temperature of the system above the dew point of the ambient air. This will keep condensation from forming on the outer surface of the insulation, avoiding safety hazards and preventing dripping condensate on buildings or electrical equipment. It’s essential to agree on what percentage percentage of time condensation is acceptable.

In hot and humid outdoor environments and during rain, it’s virtually impossible to prevent condensation 100 percent of the time. If the insulation thickness is designed to allow for an 8-10 Btu·hour/feet2 heat gain, this will be sufficient to prevent condensation the majority of the time.

Providing Process Control

Process control is a critical design parameter in many industrial applications, especially steam and critical process piping and equipment. Providing a stable temperature flow and heat loss throughout a process system in many cases is more important then any other system design.

When designing for process control, other information is also necessary, such determining what heat loss or temperature must be controlled. What’s the length of pipe and size of equipment? How is the piping and equipment supported? Are they on insulated shoes, vessel skirts, legs or other components? Also, any protrusions, if any, should also be accounted for in the heat loss.

Freeze Protection

Freeze protection can be maintained by fluid flowing insulation or by insulation with some form of additional heat input. Insulation alone can’t maintain a temperature. It will delay the time required for a fluid to reach a design temperature, but it can’t stop it.

In the Gulf Coast region, generally most stagnant water lines in sizes 6 inches and smaller should be heat traced and insulated. Lines between 8 feet and 12 feet need insulation only.

Freeze protection could also refer to prevention of product solidification. In product solidification, most times additional heat input is required to replace the heat loss through the insulation. For example, heavy fuel oil might have to be maintained at 250 degrees F and will require additional heat input to replace the heat loss through the insulation

Noise Control

Environmental acoustic issues can be addressed in thermal insulation system design. However, serious noise problems should be treated as a separate and independent study.

Sound attenuation is a natural by-product of the insulation design. Because of their sound absorption characteristics, some insulation and accessory products provide greater sound attenuation than do others. Mineral fiber products are among the best thermal insulation materials for sound attenuation.

The jacketing material used to cover the insulation can play an important role in sound attenuation. A fabric reinforced mastic finish over insulation has better sound absorption properties than metal jacketing. Metal jacketing may also be purchased with a loaded mass to reduce noise.

Fire Protection

As a general rule, insulation materials are better suited as insulation than as a fire protection product. However, the American Petroleum Institute (API) acknowledges conditions under which some insulation materials may provide "credit" in the design and sizing of pressure relief valves. API Recommended Practice 521 states insulation system requirements. Included is a requirement that the finished insulation system will not be dislodged when subjected to the fire-water stream used for fire fighting, either by hand lines or monitor nozzles. Most insulation systems used in fire protection are metal jacketed with stainless steel jackets and bands which meet these criteria.

Physical and Mechanical conditions

Physical and mechanical conditions also play an important part in insulation system design. Indoor applications generally don’t require the complexity of outdoor designs. Similarly, below ambient applications are more complex than hot applications. The physical abuse and mechanical conditions that an insulation system is subject to are also important to consider during design.

Rigid insulation is resistant to deformation when subjected to foot traffic. Compressible insulation doesn’t offer the same resistance to such loads. Areas that experience loads or repetitive personnel access/use will require a firmer system than inaccessible areas. Piping used as ladders/walkways and riggings hung from pipes and horizontal surfaces subject to vibration/loads are examples where rigid insulation is required. Compressible insulation is required for filling voids and closing gaps in insulation, which allows expansion, contraction, or movement of rigid insulation.

Mechanical abuse should be considered on a case by case basis. Insulated items located in high traffic areas should have a structure such as a platform or similar protection, to avoid having personnel stepping directly on insulation.

Insulation Materials

There are many types of insulation materials available for industrial application, though there are too many to discuss in detail here. A few of the most common industrial insulations and types will be described. These are:

  • Calcium Silicate
  • Cellular Glass
  • Fibrous materials
    (fiber glass and mineral wool)
  • Perlite
  • Polyisocyanurate foam

The "Insulation Material Specification Guide" from the National Insulation Association’s National Insulation Training Program, which may be obtained by contacting NIA (www.insulation.org), gives a quick comparison of ASTM values for these and other insulation materials.

When comparing material properties, keep in mind that ASTM test methods are usually performed under laboratory conditions and may not accurately represent field conditions, depending on process temperatures, environment and operating conditions.

Calcium Silicate

Calcium silicate insulation is a rigid dense material used for above ambient to 1,200 degree F applications. This has been the industry standard for high temperature applications. It has good compressive strength and is noncombustible.

Cellular Glass

Cellular glass insulation is also a rigid dense material normally used in the temperature range from minus 450 degrees F to 400 degrees F. It’s of a closed cell structure, making it preferred for low temperature application and for use on services where fluid absorption into the insulation could be a problem.

Fibrous Materials (Fiber Glass and Mineral Wool)

Fiber glass and mineral wool are actually two separate and distinct types of insulation. However, many of their applications and physical properties are the same. These products are generally not used where mechanical or physical abuse could occur. It should also be understood that although they may be used in high temperatures, some of their physical and acoustical properties maybe lessened.

Perlite

Perlite insulation is generally used in the same type of applications as calcium silicate insulation. However, it’s somewhat lighter in density and lower in compressive strength then calcium silicate. It’s treated with a water inhibitor, preventing the material from absorbing atmospheric moisture during storage and installation.

Polyisocyanurate Foam

Polyisocyanurate foam insulation is used in temperature ranges between minus 200 degrees F to 300 degrees F. It has very good thermal properties and is 90 percent close cell. In cold service application it requires multiple layer application because of its contraction characteristics.

Accessory Materials

The accessory materials used as a part of the insulation is as important as the insulation material itself. If the wrong accessory material is picked, the system will not provide the required performance.

Normally used accessory materials include acrylic latex mastic, aluminum jacketing, stainless steel jacketing, stainless steel bands and screws, hypalon mastic and electrometric joint sealers.

Metal jacketing is preferred to mastic for most outdoor applications because of its durability. Colored jacketing should be used for cold service and personnel protection insulation to reduce surface emittance from 0.01 for new aluminum to 0.8 for colored aluminum, which will reduce insulation thicknesses.

I have discussed several subjects which must be considered when designing an insulation system. I’ve also tried to show that there’s more to designing an insulation system then picking a material and covering it with weatherproof jacketing.

In the United States, energy conservation, power capacity and greenhouse gas emission reduction are serious issues. They have affected almost every industry in the country, including those involved in power generating. New boiler construction was almost non-existent for 10 years. Now, seemingly overnight, everyone needs to build a new steam-generating boiler. Designing, manufacturing and constructing a 600-megawatt boiler used to take three years. Now it can be done in less than two. Government mandates on NOx emissions have also put a lot of pressure on scheduling, from design to construction. When schedule is the driving issue, it affects every component, including insulation and lagging.

In the "old" days it was a common construction practice for the insulation and lagging to start after all the equipment was erected. (See Figure 1.)

Today it’s rarely done that way. To meet schedule requirements, flues, ducts and equipment are being insulated on the ground with pre-insulated lagging panel systems (sometimes referred to as packed panels). (See Figure 19.)

Panel Issues

It may help some readers to review a few items.

Pre Insulated Lagging Panel System

A pre-insulated lagging panel system is a lagging and insulation system that consists of a shop-or-field fabricated aluminum-lagging sheet lined on the backside with insulation. The aluminum lagging is laid face down on a table in the shop. The insulation pins are welded to the lagging sheet on approximately 12-inch centers. The insulation material is impaled over the pins. Aluminum foil is placed over the insulation. The foil will reflect some of the heat back in and is equivalent to about a 1/2 inch of insulation. A galvanized mesh (generally 2 inches x 2 5/8 inches, 16 gauge) is placed over the foil.* The mesh keeps the insulation in place, which will prevent the fibers from settling to the bottom. A 2-1/2 inch square speed clip is placed on the pins, which are bent over to hold the panel together. This insulated lagging sheet or panel will then attach to the outside of the stiffeners directly or to a sub system made from angle iron.

(*The aluminum foil and the mesh will help retain the integrity of mineral wool board insulations. The foil could be eliminated if using fiberglass insulation and the application is for low temperatures of 350 degrees Fahrenheit [F] and below.) (See Figure 2.)

There are several important panel issues to know.

  • A pre-insulated lagging panel utilizing a 4-inch thick mineral wool, 8-pound density insulation and .032-inch box rib aluminum lagging weighs approximately 4-1/2 pounds per square foot. This weight is important to know when calculating crane sizing for lifting the ground-insulated pieces to elevations. Ten-foot long panels can be very difficult to handle because they will weigh as much as 200 pounds.

  • Clearances also have to be observed due to the entire insulation and lagging system being installed outside the stiffeners.

  • Material storage space must be readily available, because a pre-insulated lagging panel system is a pre-designed system and the panels must be made in quantity and ahead of time. All of the stored panels must be weather protected, because water damage is the leading insulation killer. (See Figures 3 and 4.)

    Panel vs. Conventional

Since the early to mid 1970s, boilers and their associated hot flues and ducts (above 350 degrees F) were almost always insulated and lagged using a conventional insulation and lagging system*. Some original equipment manufactures of boilers for instance, never used a pre-insulated panel system on their boiler and furnace walls, but did use panels on some hot flues, ducts, air-heaters, economizer casings, and penthouse vertical walls from 1968 to 1975.

(*A conventionally insulated and lagged system is a system where each component will be attached separately. In most cases, due to the size of the stiffeners being designed today a sub-system (inner insulation support or H-bar type system) may also be required. One such conventional system (and there are many systems out there) is the insulation pin and sub-girt system**.)

(** The insulation pin and sub-girt system utilizes 10-gage insulation pins and a perforated 3-inch wide sub-girt or hat channel to attach the lagging. Insulation pins are laid out (6-inch horizontal spacing) so the lagging will have sufficient support based on the wind-loading span. After the insulation has been installed (impaled) over the insulation pins a sub-girt channel or hat section will be installed to these pins by using an insulation speed clip. The lagging will then be screwed into the sub-girt.) (See Figure 5.)

The Changing of the Guard

It’s this conventional system, as described previously, that’s now being replaced by the pre-insulated lagging panel system for almost all hot flue, duct and selective catalytic reduction systems. This is due in part to the very tight erection scheduling, requiring ground assembly and the very large stiffeners being designed on the equipment. Up to now, panels have been used on some hot flue systems operating as much as 750 degrees F, but they haven’t been utilized on boiler and furnace walls. Cold flue and duct systems operating at 350 degrees F and below have utilized pre-insulated lagging panels for more than 30 years. (See Figure 6.)

When utilizing a panel system on hot flues and ducts and equipment, including a selective catalytic reduction system, you should take note of the following information:

  • Ensure that adequate supervision and attention is paid to the design of the pre-insulated panel system and the installation.

  • Ensure that adequate clearances are kept between all obstructions.

  • When ground assembling of equipment, ensure that enough un-insulated area is left exposed to allow the welding or attaching of the insulated flue or duct pieces. (See Figures 7 and 8.)

  • Ensure that you have accounted for the weight of the panel system to the flue or duct piece that’s being lifted.

  • Don’t use pop rivets or a Hilti type fastener system if there’s a lot of vibration expected during operation.

  • Ensure that the panel system can resist 30 psf positive and negative wind force without loss of weather barrier integrity.

  • Ensure that panels are properly flashed and sealed around penetrations such as support brackets, poke holes, and man-ways by using mitered edges and segmental cuts to reduce caulking and buttering to a minimum (See Figure 9.).

  • Ensure that every penetration through a vertical surface has a "drip-lip" type flashing and is caulked (See Figure 10.).

  • Ensure that all vertical surfaces, including hoppers, with vertical runs greater than 10 feet long have a thermal barrier installed to prevent stack effect of hot air. (See Figure 11.)

  • Ensure that closure strips are used at all open ends of lagging that aren’t otherwise flashed. Closure strips must be recessed back from the extreme edge of the sheet and must be properly held or supported to prevent slippage.

    Expansion and Contraction and Caulking

All lagging panels must be applied over areas to present a true plane. Then it’s stiffened and fastened on adequate centers to prevent excessive deflection or "oil canning" when hot or cold. (See Figure 12.)

Expansion and contraction requirements represent a major problem for lagging panels. Necessary provisions for expansion and contraction must be provided to maintain a neat and proper design when in service. It’s critical to note that when a panel system is being utilized today, a large portion of the work is being done on the ground. The expansion areas and tie in areas will be finished at elevation after the flue or duct pieces have been lifted and installed. Here are some useful tips to follow:

  • Sealing by welding, soldering, or caulking is permissible consistent with temperature limitations and expected expansion and contraction.

  • Attachments for the panels shall be spaced in set patterns both vertically and horizontally to present a uniform appearance. They shall be located on centers to prevent rattling or "oil canning" due to expansion or vibration and maintain the specified wind loading.

  • Lagging panels when used over expansion joints shall be designed to provide movement equal to the expansion of the joint covered.

Panels on Boiler and Furnace Walls

Since the mid to late 1970s, pre-insulated lagging panels have been used predominately only on flues and ducts operating at 350 degrees F or below. Prior to that, panels were being used on some hot flues, ducts, and equipment but, not on boiler and furnace walls. Scheduling was not an issue at the time. The insulation work was done during the final phases of construction at elevation, and therefore the panel design and installation became impractical. The combination of long erection schedules, and the material handling and labor production problems eventually led to panels being, for the most part, eliminated from the construction options for installing insulation and lagging on flues, ducts and equipment operating above 350 degrees F.

Today, due to the tight erection schedules and ground assembly, panel systems are again being considered on all surfaces including boiler and furnace walls. There are many applications where this might be a viable option. These include:

Shop installation

In shop installation, the boiler tube panels with buckstays attached would be laid out on a shop floor, and the entire system of tube panels (with the insulated lagging panels attached) are shipped directly to the job site.

Hot installation

In hot installation, when the boiler is in operation, panels could be used in lieu of a conventional application. Hot installation (installing insulation and or lagging when the boiler is running) requires specific expansion designs. In my opinion, I think pre-insulated panels would be a viable alternative to a conventional system. The expansion would be designed into the panel construction.

However, there will always be concern in the industry about material handling of panels (size and weight of a panel), wall penetrations, protrusions and doors. However, I don’t believe that the problem about penetrations, doors, and protrusions is limited to just pre-insulated panels. Penetrations, doors, and protrusions exist on only about a third of all boiler and furnace wall surfaces, and they must be addressed even when installing a conventional insulation and lagging system. To me, the approach would be the same for installing panels as it is for a conventional insulation and lagging system when dealing with any type of penetration, door, or wall box. The ease or difficulty as to how that would be done with panels versus a conventional insulation and lagging system isn’t the point of this article. As for the size and weight problem of panels, that’s an issue of concern whenever you’re installing a panel system, and I see it as no more difficult to do or overcome than when installing panels on SCR flue-work.

To install a panel on a boiler or furnace wall will require a special attachment such as the one shown on the following drawing. These attachments will be required at the top and bottom areas where the panel will be attached. Wherever support spacing dictates, additional support rows should be added. The advantage of using a panel design is that the supports can be installed in the tube panel shop prior to shipping to the field for erection.

The pre-insulated lagging panels must be designed and installed to fit between buckstays and flashed and or attached at the buckstays as shown on the following drawings: (See Figures 13, 14 and 15.)

Significant Pointers

The advantage of installing a pre-insulated panel system on flues, ducts, or boiler and furnace walls, in lieu of a conventional insulation and lagging system, is the potential for lower installation cost. The panels can be fabricated at an outside fabrication shop more cheaply than using field labor. Then the panels can be installed in one operation. The problem with panels is that everything (design, fabrication, and installation) must be done correctly for the system to work. When something goes wrong with a panel system, the problems are magnified when compared to problems on any conventional system.

A panel system will expand more than a conventional system because the entire system (insulation and lagging) must expand together. The expansion must be incorporated into the panel sub system and is critical for proper expansion. An example: in a system operating at 850 degrees F, each panel must be able to accommodate 1/2 inch of expansion in the direction the ribs are running. The horizontal laps must not be fastened together so that each row can move independently to the adjacent rows. Each joint must be fitted tightly so that when the unit goes into operation, large voids aren’t opened. The horizontal expansion isn’t a specific problem because, like any conventional system, the "accordion effect" of the ribs take up the expansion.

Panel systems require extensive lay down and storage area because they must be manufactured ahead of time and stored at the site. Because panels are heavy, the storage area should be close to the work area, and all the panels must be marked and or tagged for the location that it was fabricated and designed. Therefore, although panels are cheaper to install, they require more handling and storage needs. (See Figure 16.)

Each panel is specifically designed and fabricated for a specific location, and must be installed in sequence (similar to laying brick). You must start at the bottom and work across each row before you can install the next row. This means that the erection sequence must be figured into the entire construction schedule. A conventional system is more schedule-friendly than a panel system. It happens many times when the construction schedule was changed and thus caused large amounts of surface area needing to be insulated (and lagged) in a very short period of time. Panel installation doesn’t lend itself to quick installation because panels are a pre-designed system and require extensive material handling.

The type of insulation used on a panel system is also critical. On a low temperature application of 500 degrees and below, fiberglass or mineral wool type products can be used (and have been for more than 30 years). The fiberglass is half the weight of the mineral wool products, and makes the panel easier to handle. However, it’s not recommended using fiberglass on applications above 500 degrees F due to the lower compressive strength and lighter density. At higher temperatures, the fiberglass allows heat to migrate up within the insulating material itself, and can cause the much lighter insulation to shrink more than the mineral wool products. This increases the potential for hot spots on the lagging surface caused by heat escaping through the cracks created by the shrinking fiberglass material.

Money Saving Tips

Shop fabrication of panels can save money because most shop labor costs are cheaper than field labor. However, it’s not recommend because shop-installed panels can get easily damaged during shipping. It’s recommended to have the sub-girt system for the support of the panels to be shop installed. This will create an estimated savings of approximately 0.75 per square foot in field labor cost. Ground assembly is another money saver, but only if the piece to be covered is off the ground for ease of panel installation. Estimated labor savings could be $1 to $2 per square foot compared to installing the panels at elevation. (See Figures 17 and 18.)

Conclusion

Pre-insulated lagging panels can be an excellent insulation and lagging system for use by the power generating industry, as long as attention is given to detail and design. Pre-insulated lagging panel systems are a pre-engineered system that requires very clear and defined drawings for installation. The panels must then be manufactured with close attention to the tight tolerances, the erection schedule requirements, the installation, the supervision and the material handling and storage. An assortment of things can go wrong with a panel system. However, if properly designed, manufactured, installed, and supervised, panels can help industry meet their scheduling requirements and get their steam-generating boilers back on line and on schedule.

Gary Bases is president of BRIL, inc., an independent consulting firm specializing in brick, refractory, insulation, and lagging where energy saving solutions are possible. Contact him at (330) 665-2931 or brilinc@raex.com.

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Figure 19

The market demand for general contracting and construction management services has changed significantly with the compounding effects of the events of Sept. 11, 2001, and the already slowing economy. Of course, this trend has been exacerbated by the sting of recent accounting scandals, the lack of investor confidence, and the continuing spiral of the stock market. But how are these broad market factors affecting contractors, and what actions are they taking to respond to the challenges?

As contractors continue to see their backlogs dwindle, many are taking time to evaluate and scrutinize their business. Contractors in weak markets are looking to reposition themselves in stronger markets, such as education, where capital spending will be available. This refocusing of strategic plans and entrance into hot markets is increasing competition in those markets and, in some cases, driving fees down. Balances sheets and other financial statements are being carefully reviewed. Contractors are taking cautious measures, such as securing long-term debt for future use.

Renovation and Retrofit

Once thought to be a niche market, the renovation and retrofit market is gaining strength. Many owners that had been planning new greenfield projects are not cutting capital expansion budgets and renovating existing faculties to stay satisfy short-term needs. Although these major projects may be revitalized in the future, interiors and tenant-upfit contractors are reaping the benefits from this shift in resources.

While this expanded market opportunity has fueled growth for existing interiors contractors, it has encouraged traditional firms to add new services for their clients. Creative firms are helping owners find solutions to a wide range of problems beyond the short-term need of locating their people and operations. This shift in focus requires a sophisticated approach to providing project management services for customers that are demanding more. Although some firms will make the transition easily, many contractors accustomed to operating in the adversarial hard-bid environment will find it difficult to reprogram their operations team to be more responsive to clients’ needs. Long-established interiors contractors are concerned that the increased attention to this market by the large general contractor/construction manager contingent is rapidly commodifying the fees and prices.

Leading-edge contractors recognize the importance of having a project culture that’s not contentious. They are developing and implementing training programs to sensitize their project managers and superintendents to be more empathetic to the needs of the customer. In fact, they see this as an opportunity to enhance margins by anticipating and responding to customer needs.

However, this approach requires a discipline to correctly identify, document, and price customer-driven change orders with the appropriate overhead, burden, and margin included in the price of the additional project scope. Too many times, field managers are focused on the project schedule and are reluctant to ask their client for additional fees, even when they are entitled to them. This loss of potential revenue and profit can be overcome with the installation of appropriate systems. With the controls in place, contractors can provide training to build the confidence and ability of their project management teams to educate customers on the economic benefits that outweigh the costs of their requests. Contractors should never be afraid to ask for and receive extra compensation for additional work.

Shifting Targets

With the decline of certain sectors such as office, institutional, and hospitality, contractors must find new opportunities to replace lost backlog. Many firms are shifting resources to selected public sectors such as education and infrastructure work. In response to the demographic demand, several states are launching massive capital expansion programs at all levels of education, including K-12, community colleges, and higher education.

Many firms that avoided public sector work in favor of private negotiated projects are now chasing school work. The K-12 market has traditionally been a hard-bid market with lower margins and lower fee opportunities. Many states are responding with more progressive and flexible procurement processes in an effort to attract the best firms. The result is a better value for state taxpayers, improved schools for future students, and more work for responsive contractors. In other states, hidebound procurement results in quite the opposite, making this a market with spending but significant margin challenges.

Community colleges accustomed to "starvation" budgets will have significant funding for construction as they prepare for the next big population wave now moving through K-12. Without systems in place to administer construction programs, these schools will likely look to contractors for help. Opportunities for alternative delivery methods will be available.

Higher education has historically taken a classical approach to construction, and significant funding is presenting new opportunities for traditional contractors. For example, the University of North Carolina system successfully campaigned for the passage of a $2.5 billion bond referendum to fund expansion on all 16 of its campuses across the state. When coupled with funding from ongoing resources, this funding results in a $6.7 billion program over the next seven years.

Building Project Management Competence

As more general contractors move away from self-performing any field work and the proliferation of construction management firms continues, project managers are increasingly becoming "business managers" instead of "builders." Although their formal education and training may not have prepared them for this transition, it’s the role they must play on a regular basis. Many companies are frustrated with the lack of business acumen that today’s young project managers exhibit. Obviously, this lack is partly due to the typical education that accompanies these people-either engineering or construction management. However, some universities are moving toward a more well-rounded approach to educating their future constructors by offering or even requiring some business courses before granting a degree-particularly in the construction management curriculum.

Construction companies must understand that their main purpose, and therefore their opportunity for differentiation, is to find solutions for their customers. This applies not just in the building sense, but even more so in choosing the correct delivery mechanism for a particular customer’s need-for example, in a design/build environment, finding a creative financial solution to a budget issue that pleases the customer, architect, and the contractor.

The ability to persuade others and negotiate a plausible solution that makes everyone feel food about the outcome is a critical skill that too few project management personnel possesses. These "softer skills," such as building customer relations, negotiating contracts or change orders, project financial and cash management, and their own individual project leadership skills are often derided by "true builders" as irrelevant. In fact, these skills can have the largest influence on customer satisfaction and the final profitability of the job. If project managers were savvier about how to manage their costs on projects, they would have less "profit fade" and increase the final profit margin an their respective projects.

Certainly, project managers must have the technical and construction knowledge required to build a project. However, the field superintendent can be the primary technical resource while the project manager is busy managing the project from an administration and customer perspective. In owner surveys that have been conducted by FMI over the past five years, a trend that continues to grow is that owners look to the project manager or project executive as their single source of accountability for all things that happen on their project. Therefore, the project manager must be a multi-faceted individual who can deal with the people, financial, and customer-related issues that arise on a project as easily as he or she deals with the construction issues that regularly present themselves.

General Contractors and Self-Performed Work

General contractors may decide to self-perform a larger portion of the contracts they acquire to gain more control over the critical path, to secure additional margin, or to compensate for a lack of capacity in the subcontractor market. Contractors typically self-perform concrete forming, pouring and finishing, carpentry and interiors, and even landscaping to finish the project. In fact, one contractor, Kinsely Construction in York, Pa., has four separate divisions in additional to its general contracting company that provide everything from architectural design services and site work to mechanical systems and electrical installations. These divisions allow Kinsley to control the coordination among these critical trades and provide significant value for its clients.

Some firms have made a conscious decision to add to these services in order to be more responsive to the needs of their clients. These firms are usually dominant players in the local or regional market. For example, Pepper Construction Group, a Chicago-based general contractor, has an active concrete division that’s a strong contributor to overall corporate performance. This profit center gives Pepper more control over the early phases of the project schedule.

However, the majority of contractors continue to avoid labor risk. The advent and growth of white-collar management has been a direct result of this risk-aversion. Program managers, construction managers, and general contractors gain value-added fees from the owner-typically a combined 15 percent -with little assumed risk.

Which firms were making the most money during the recent 10-year boom? It wasn’t general contractors (GC) and construction managers (CM). While mid-sized to large GC’s averaged about 1.5 percent to 2.25 percent and CM’s limped along at less than 2 percent fees on major projects, specialty trade contractors generated 10 percent to 15 percent gross margins.

When asked how they get such relatively high margins, subcontractors respond with the fact that they manage all of the productive resources such as direct labor and materials, and thus deserve to reap the reward that’s commensurate with assuming that risk.

Issues for Specialty and Trade Contractors

Subcontractors as a group are diverse and unique. The market challenges, economic drivers, and strategies for the future differ based on specialty. But similarities are also shared. We see these main issues impacting specialty and trade contractors as a group.

Technology

Mechanical and electrical contractors are battling in the marketplace with manufacturers to determine who will "own" the building technology package. The combination of technology-security, controls, fire protection, etc.-bring an overlap of expertise with these three groups. Manufacturers see the building technology package as an opportunity to grow market share and expand service offerings. Mechanical contractors see it as an extension of their traditional work. And electrical contractors view it as a growing piece of low voltage work.

Field software utilization remains primarily focused on scheduling, e-mail, spreadsheets, and word processing. Substantial investments in systems and software in the field remain a tough sell. For many subcontractors, real-time filed information for costing and payroll remains a future promise.

Cell phones, pagers, e-mail, personal digital assistants (PDAs) and digital cameras lead the list of field technology tools. E-mail remains mostly tied to desktop applications, but the introduction of PDAs is taking handheld devices from an electronic to-do list to a real-time productivity tool tracking materials, labor, and time.

Real-time information is more likely to be achieved as contractors replace legacy systems with enterprise-wide systems. The enterprise system combines customer relations management, accounting, order entry, and other functions into one computer system so real-time information is available. The old legacy systems, which often involve re-keying of information, have not been able to provide this integration. Contractors of all sizes will continue to acquire and implement these systems.

Global positioning systems (GPS) are being used on heavy equipment and ready-mix trucks to streamline trip times and expedite productivity. Watch for GPS applications to gain in popularity for building layouts.

Emerging technology includes barcodes for use on project sites and during service calls. Field service technicians use barcodes to access work order information, track tools and equipment, and expedite the billing process. Field applications include monitoring material usage and tool inventories. One contractor using barcode technology cut the time needed to inventory tools coming back from major projects from weeks to days.

Radio tags are likely to be widely used in the near future to know who and what has been brought onto the construction site. The tags track movement, increase security, and allow for simplified paperwork.

Technology is also having an impact on the services specialty contractors are being asked to provide. Smart buildings will be able to sense who is on site and cater to owners’ unique workplace-environment issues. Security challenges of moving in and out of high-security areas will be easier. In the case of emergencies, the building’s system can track where people are and help determine the appropriate response level.

"Technologist" may well be the hot future construction position that changes the way buildings are built. A technologist will be the person-perhaps on the architectural team, the engineering team, or maybe even on the GC/CM/subcontractor team-who focuses not on running information technology, but on bringing the most up-to-date technology to the building even before construction begins.

People

Human assets are the key building block for all specialty contractors. Balancing the needs of generations, overcoming the labor shortage, and developing their people in today’s competitive market are key challenges.

However, specialty contractors’ approach to developing their human assets remains diffused and too often ineffective. Craft labor training grew in success and importance in the past decade of economic expansion. The same can be said for safety training. What continues to lag is the growth and development of management, leadership, and customer-relations skills for field and office personnel.

Corporate "universities" are becoming the battle call of subcontractors large and small. More than a training class, corporate universities are focused on creating an ongoing process to grow the skills of the organization. With the continuing flattening of corporate organizational structures, growing people’s abilities is a key to ensuring a competitive advantage in the market place and achieving high levels of retention.

The labor shortage has cooled with recent softening of the economy, but the underlying challenge of finding talented people for the construction industry remains. Demographics are going to continue to present a problem even though the current market might alleviate the situation for a few years. The small "Generation X" (born between 1965-1980) is unable to fill the ranks of the aging Baby Boomers (born between 1946-1964). The problem will likely persist until late in the decade when the larger "Generation Y" (born after 1980) will begin entering the labor market in force.

The industry’s poor image continues to remain a hindrance to attracting talent. The industry hasn’t been competitive in attracting new talent in management or labor, and as a result, the average age of the industry’s workforce continues to increase. Part of the problem is that in this information economy, the industrial work option of construction does not appeal to most young people.

Subcontractors are changing internal systems to meet the needs of the younger generations in the workforce. Reward systems, sharing of information and the creation of structured career paths are a few of the tools subcontractors are employing for recruiting and retention.

Two years ago, finding the time for training was difficult given the long hours worked in both the field and the office. Today, the concern is finding the money to spend on training. Though easy to continue to delay training due to short-term business issues, today’s top subcontractors are making training and development a top priority in all levels and areas of their companies.

The average age of the construction workforce continues to increase. Subcontractors are particularly vulnerable to this problem due to the labor intensity of their field forces. Expect more back, elbow, and knee injuries as the workforce continues to age.

Compensation pressure is off due to the softer labor market in mid-to late 2002. Companies are using this time to reassess their compensation packages and bring into alignment their recent hiring practices. Over the past few years, it wasn’t uncommon to have to offer compensation rates to new hires similar the rates for existing staff.

Human resources departments are evolving from compliance and tracking functions to operating as a strategic partner to senior managers. The focus is shifting from managing one piece, such as compensation, to a holistic process in which management looks at everything affecting the performance of the organization’s people. Subcontractors are quickly learning how to embrace this new expertise in their planning and decision-making processes. The additional focus on risk management by human resources has turned into a key profit booster and retention tool.

Field Management

Labor-intensive subcontractors are leveraging small percentage improvements in labor savings to yield significant improvements in bottom-line results. Proper planning and elevated communications lead the list of techniques generating the greatest bottom-line impact.

Material-intensive specialty contractors gain productivity through proper planning to minimize the time crews spend waiting for materials. An example is an electrical contractor whose motto is "eight hours of materials within 10 feet of the workers that need them." Another contractor slogan is "Keep the welder welding."

Keeping field forces informed, trained, and motivated helps improve productivity. It’s now commonplace for field foreman to have access to full cost estimates and installed work to date. Subcontractors are thinking of ways to continuously keep the field informed on the progress being made on the job – both when ahead and when behind budget.

Post-job reviews are once again gaining in use. The focus of these reviews is to ensure that challenges, lessons learned, and best practices are captured and used on futures projects. Also, a routine part of the process is a review of what the customer wanted and their level of satisfaction at the end of the project.

Marketing and Business Development

Subcontractors who focus on public work have faced increasingly steep competition as the private construction market cooled in late 2001 and 2002, and margins were down for fiscal year 2002. Many projects earlier in the year were put on hold, and some were even cancelled. The result is that subcontractors are scrambling to find work, putting downward pressure on prices. Not finding the plentiful work of a few years ago, subcontractors chasing private work have stepped back into hard-bid, public construction in an attempt to keep their people busy and fill gaping holes in backlog. Six to 10 bidders typically bid on a public project, and that number is growing. This growing competition will affect profit margins. At the level of 10 bidders, the probability of achieving a margin is close to negligible.

Backlog is holding within 20 percent of the record high year’s volume. The challenge is that profit margins for backlog work are down. Subcontractors are looking for opportunities to grow profit margins through up-selling options on projects, pursuing change order, and continuing to elevate field productivity. The market pinch for subcontractors will ease in 2003. In most parts of the country, subcontractors will enjoy a recovery in late 2003 and early 2004.

Some customers, also impacted by the soft economy, are asking subcontractors with which they’ve had long-term negotiated relationships to bid jobs. Budget crunches have encouraged some customers to ask general contractors to bid on projects that would have been negotiated in the past. Motivated by the bid competition, general contractors and construction managers are putting additional pressure on the subcontractors to cut profit margins and shorten the construction timeframe.

The softened economy has reduced revenues for most subcontractors. However, although it’s easy to slip into concern over the financial health of a company due to the revenue lost, most subcontractors were projected to enjoy their second-best year on record in 2002. For other subcontractors, their 2002 revenue more closely reflects 1998 and 1999-the 2002 market is down from the prior year but still remains strong. The current challenges of getting work will be short-lived and provide subcontractors an opportunity to refine their effectiveness at getting work. The business development sophistication of specialty contractors has grown tremendously over the past several years. Today subcontractors create proposals and presentations that "sell" their proposed solution to the customer and general contractor. Proposals have grown beyond simple response to RFPs to become a robust sales tool positioning the value-added services being provided.

The increasing cost of insurance and bonding is limiting the profits on projects. Used to the ease of getting bonds on projects, many successful subcontractors are facing a challenge not experienced in the past decade – lack of bonding capacity. Those with sufficient capacity find themselves with a short-term market advantage over competitors because bonding is an entry barrier to many big projects.

Subcontractors need to be proactively working to build strong relationships with their bonding, insurance, and banking representatives. Now is the time to expand these relationships outside traditional providers so there are backup plans in the event the primary relationships quickly change.

Technology Comes to Business Development

The same technology that allows an avid sports fan to "see" the view from their seat before the stadium is completed allows customers to take a visual walk-through of a project prior to construction. Changes can be quickly made before substantial costs are incurred to tear out and replace installed construction. This three-dimensional visual capability will be a growing tool in subcontractors’ marketing arsenal.

Subcontractors are fighting against the compartmentalization of their work. Traditional packages are being broken down and bid separately. The intent is to provide a cost advantage to the project. However, the increase n the number of specialty contractors on site complicates coordination.

Specialty trade associations, which are struggling to retain and grow membership, are looking for value-added services for members outside the traditional political and labor negotiation. Union trade associations in many cases have higher revenue and member retention than open-shop associations. Associations are challenging members to volunteer for committees and be active in the association. The older generation was brought up to "give something back," but it’s unclear if younger generations are willing to give up personal time to serve in associations. Many people who aren’t active cite "life balance" as a primary reason.

Design/build continues to be a good opportunity, and subcontractors have enjoyed the opportunity to compete on a basis other than price. However, this delivery method has its warts. Design/build changes the economic model of a contractor that has previously relied on hard-bid work. Design/build projects have longer lead times and greater up-front costs without a guarantee of securing the work. It’s essential for subcontractors to balance the benefits of design/build with the required investment of time and resource.

Subcontractors are experimenting with the design/build market in a cost-effective way by forming alliances with architecture/engineering firms. The trend of A/E firms entering the market as design/build contractors is cooling rapidly.

Architects and engineers, pressured to get their fees lower and speed design, are turning out construction documents with less detail than in the past. Subcontractors are having to detail higher amounts of their work and resolve unexpected conflicts in the field. The impact on field and office productivity is substantial. Subcontractors are responding by adding detailers and expanding their pre-job planning efforts. In some cases, subcontractors are finding that by redrawing mechanical, electrical, and other systems, they can give their field workers clearer direction and ultimately raise productivity levels.

Giving customers an excuse to buy on something other than the lowest initial cost continues to challenge many subcontractors. The inability to differentiate their service offering keeps thousands of subcontractors competing in hard bids. The answer is for a cross section of managers to come together in a planning venue to consciously create a competitive difference in pursuing jobs. If that difference resonates with targeted customers, the subcontractor wins. If he doesn’t, the differentiation effort increases the cost of doing business without providing a bid-day advantage.

Adapted from the 2002-2003 U.S. Markets Construction Overview. Reprinted with permission from FMI Corp., (919) 787-8400. For more information, visit www.fminet.com or call Angela Blackburn at (919) 785-9220.

Founded in 1898, ASTM International is a not-for-profit organization that provides a global forum for the development and publication of voluntary consensus standards for materials, products, systems, and services, including thermal insulation.

Formerly known as the American Society for Testing and Materials, ASTM International provides standards that are accepted and used in research and development, product testing, quality systems, and commercial transactions around the globe.

ASTM C16

ASTM C16, the committee on thermal insulation, last met in September 2002, in Dallas for its semi-annual meeting. As usual, there were a number of different task group meetings. Among the items discussed were existing and proposed standards, subcommittee meetings, the main committee meeting and a Monday night forum on the National Insulation Association’s (NIA) National Insulation Training Program (NITP). In this article, we’ll discuss the ASTM committees, with an overview, committee scopes and a summary of the activities.

Committee Overview

The ASTM Committee C16 on Thermal Insulation was formed in 1938. The C16 committee meets twice a year, usually in April and October, with approximately 120 members attending for three days of technical meetings, capped by a discussion on relevant topics in the thermal insulation industry. The committee, with a current membership of approximately 350 people, has jurisdiction of more than 134 standards, published in the Annual Book of ASTM Standards, Volume 04.06. These standards have and continue to play a pre-eminent role in all aspects important to the thermal insulation industry, including products, systems, and associated coatings and coverings, excluding refractories.

Committee Scope

According to ASTM, the scope of the C16 committee "shall be the development of standards, promotion of knowledge, and stimulation of research pertaining to thermal insulation materials, products, systems, and associated coatings and coverings, but not including insulating refractories. These activities shall be coordinated with those of other ASTM Committees and national and international organizations having similar interest."

Scopes of Subcommittees

C16.16: US Delegation to ISO/TC 163

For this subcommittee, the scope is standardization in the field of thermal insulation, including terminology, test methods, calculation methods and specifications for thermal insulation materials, components, constructions and systems, including a general review and coordination of work on thermal insulation within ISO. Excluded are test and calculation methods, which are treated by other ISO technical committees after agreement with these technical committees.

C16.20: Homogeneous Inorganic Thermal Insulations

The scope of this subcommittee is to develop and maintain standard test methods, definitions and nomenclature, recommended practices, classifications and specifications for all homogeneous inorganic thermal insulation materials under C16.00 jurisdiction, except those assigned to subcommittee C16.21 and C16.23.

C16.21: Reflective Insulation

The scope of this subcommittee is to develop and maintain product specifications and test methods applicable to thermal insulations, which depend essentially on the reflectance of heat for their effectiveness. Test methods are those not generally applicable to other forms of thermal insulation or associated materials. Jurisdiction of this subcommittee on building type constructions include only materials or assemblies consisting of one or more heat reflective (low emissivity) surface(s), such as metallic foil, unmounted or mounted on thin membrane(s), such as paper or fibrous or foam sheets, all less than 1/8 inch in thickness.

C16.22: Organic and Nonhomogeneous Inorganic Thermal Insulations

The scope of this subcommittee is to develop and maintain standard test methods, definitions and nomenclature, recommended practices, classifications and specifications for all organic and non-homogeneous inorganic thermal insulation materials under C16.00 jurisdiction, except those assigned to subcommittees C16.21 and C16.23.

C16.23: Blanket and Loose Fill Insulation

The scope of this subcommittee is to develop and maintain product specifications, and recommended practices and test methods (when not under the jurisdiction of a methods subcommittee) for all thermal insulation materials under C16.00 jurisdiction, except those assigned to subcommittees C16.20, C16.21 and C16.22.

C16.24 Health and Safety Hazard Potentials

The scope of this subcommittee is to develop and review standards related to potential health and safety aspects associated with the installation and use of thermal insulation materials, accessories and systems.

C16.30: Thermal Measurements (Including Calculation Methods)

The scope of this subcommittee is to develop and maintain test methods and recommended practices relating to the transfer of energy within and through thermal insulating materials and systems.

C16.31 Chemical and Physical Properties

The scope of this subcommittee is to develop and maintain test methods and practices related to chemical and selected physical properties of thermal insulating materials.

C16.32: Mechanical Properties

The scope of this subcommittee is to develop and maintain test methods and practices related to selected mechanical and physical properties of thermal insulation and associated materials.

C16.33: Insulation Finishes and Moisture

The scope of this subcommittee is to develop and maintain material specifications, test methods, recommended practices and classification systems: (1) applicable to coatings, coverings, adhesives and sealants used in association with thermal insulations; and (2) involving the transfer of vapor through thermal insulation and associated materials, and involving the accumulation of moisture in thermal insulating materials and systems.

C16.40: Insulation Systems

The scope of this subcommittee is the development and maintenance of performance specifications and standard practices for thermal insulation systems. The systems include all of the individual components combined in a manner to provide an effective control of heat transfer and moisture transmission within the insulation systems under the operational and environmental conditions of its intended use. Such components, if part of the system, will include the thermal insulation, supports, securements, and protective coverings.

Overview of C16 Meeting

Most of the C16 subcommittees are involved with materials and subjects relating to both mechanical insulation and building envelope insulation. Since NIA’s member contractors, fabricators, and laminators primarily deal with either mechanical insulation or metal building insulation, this report only addresses the standards relating to those materials.

Pipe and Equipment Insulation Fabrication

The C16.40 subcommittee has been working for several years on developing a new standard on this topic. In the process, this task group (TG) has written a draft standard for fabricating cellular glass insulation only, and in the process developing another draft standard for cellular glass block only (without fabrication). At the spring 2003 meeting, the TG will discuss this draft fabrication standard for cellular glass only.

C450, "Prefabrication and Field Fabrication of Thermal Insulating Fitting Covers"

A recent ballot was held to put this standard’s adjunct on "Recommended Dimensions Standard" onto a computer disk, allowing extensive dimensional charts to be accessible on CD as a PDF file. This was scheduled to be available by the end of the 2002.

C533, "Calcium Silicate Pipe and Block Insulation"

A ballot was recently held on a revised standard, and the result was a negative vote. This was because members believed there was a need for mandatory moisture content testing to be included in the standard prior to testing. This negative was found persuasive. As a result, when SC C16.33 has completed its efforts in writing a moisture content test, it will be added to this material standard for calcium silicate.

C547, "Mineral Fiber Pipe Insulation"

A ballot was recently held on a revised standard, which resulted in a negative vote stipulating that this type of material should be required to be tested for water vapor permeability (with no jacketing). The standards committee (SC) and the main committee found this negative to be non-persuasive; the revised standard will become the new standard C547.

C522, "Cellular Glass Block & Pipe Insulation"

As with the previously mentioned C533, the TG agreed that this standard should eliminate the water absorption test (which is currently part of this material standard), when a new, stand-alone testing standard becomes available.

C585, "Inner and Outer Diameters of Rigid Thermal Insulation for Nominal Sizes of Pipe and Tubing"

The TG recently made some changes to the existing standard. These included adding a table for outer diameter tolerances, inside diameter tolerances and maximum outer diameters, while deleting wall thickness tables. This revised standard will be concurrently ballot, before C16.20 and C16.

C612, "Mineral Fiber Board and Block Thermal Insulation"

The TG is in the process of revising this standard and will have the new draft distributed for a concurrent SC and main committee ballot. This draft will include an exothermic test for products requiring a heat-up schedule in one of the types of mineral fiber insulation.

Microporous Insulation

The task group developing a new standard on this material hasn’t met for several meetings. As a result, the TG will be disbanded.

C534, "Preformed Flexible Elastomeric Thermal Insulation in Sheet and Tubular Form"

This TG recently put a new draft on a ballot, and the draft received negative feedback concerning minor changes to the material flexibility and linear shrinkage sections of the specification, which were found persuasive. The new draft incorporating the changes will be reballoted concurrently with C16.22 and the main committee prior to the spring 2003 meeting.

C1126, "Faced or Unfaced Rigid Cellular Phenolic Thermal Insulation"

A revised draft of this material standard was recently put on a ballot and received negative comments that had to be addressed in the TG meeting. One negative involved "produced with vapor barrier facing," since these facings are frequently applied by a fabricator, as opposed to the manufacturer. As a result, the TG decided to change the Scope of C1126 to read, "This specification applies to cellular phenolic thermal insulation. Boards may be faced or unfaced. Tubular forms covered by this specification shall be unfaced." Also, a note will be added, stating, "If a facer or vapor barrier is to be used for the tubular form, then refer to Practice C921 to aid material selection."

Organic Foam Insulations

In several task groups, there was discussion about upcoming changes in the type of blowing agents that will be used in the future. Some currently used blowing agents will not be allowed in the future, and will have to be replaced with alternatives. When these blowing changes occur there will be changes in physical properties of the insulations involved. Because the exact type of alternate blowing agent hasn’t yet been determined, it’s not known whether these changes in physical properties will be positive or negative. The insulation types involved are phenolic and polyisocyanurate types. These changes will occur in the next 12 to 24 months.

C168, Terminology

This TG has had on the ballot different draft definitions for "fibrous glass" and for "mineral wool." In each ballot cycle they are slightly changed, so they will again be sent to members in a slightly modified form.

Monday Night Forum

Ron King, representing NIA, addressed the Monday Night Forum. His subject was the NITP. The forum was well attended, with about 60 people present (about half of this meeting’s total attendees). The Monday Night Forum for the spring 2003 C16 meeting will address "How to Get Mold and How to Get Rid of Mold in Buildings," presented by Jeff Huddleston of Performance Abatement Services.

Spring 2003 Meeting

The spring 2003 meeting will be held at the Westin/Hyatt Crown Centers in Kansas City, Mo., April 6 – 9. The Monday Night Forum will be held April 7 at 6 p.m. at the Westin. For more information about ASTM and the C16 committee on thermal insulation, contact ASTM at (610) 832-9585 or on the Internet at www.astm.org.

INSULATE (in’ sa-lat’):

To prevent the passage of heat, electricity, or sound into or out of an area. Accomplished by surrounding area with a non-conducting material.

The above definition describes how insulation works in a nutshell. Most people in the industry know it like the back of their hand. Whether you’ve been in or around the insulation industry for one year or for 20, it should be fairly simple.

If you’re a plant engineer or facility manager and you want to find out about K or C factors, and R or U values, chances are that an industry professional can give you the scoop. What if you’re wondering about heat transfer, conduction, convection, radiation, emissivity, ambient temperature, relative humidity, dewpoint, water vapor pressure and condensation? Again, a professional can tell you all about those things, suggest the proper insulation type and assist you in finding ways to help your facility run better, while saving you energy and money.

However, even in an industry full of talented people, it doesn’t hurt to got back to basics once in a while. Maintaining a strong background in the science of insulation can ensure that customers continue to receive the best in insulation solutions.

Training programs such as the National Insulation Association’s (NIA) National Insulation Training Program (NITP) provide an opportunity for both industry professionals and end-users to strengthen their insulation knowledge. The NITP teaches a segment about "Basic Insulation Science." It covers the basic definition of insulation, and how the various factors previously mentioned determine the type and quantity of insulation that is used in a particular setting, along with how these conclusions were reached.

"Often people understand that insulation is needed but don’t know why," says Mike Lettich principal consultant with MJL Consulting and a future NITP instructor. "This results in a [sometimes] fuzzy understanding of the benefits of a proper insulation system. The ‘Basic Insulation Science’ module does just that; it provides a basic understanding of how insulation works, helping people to start to better understand its benefits."

Why the Need for Basics?

Most of us know how to drive a car, but do we really understand how it works? Well, the same questions could be asked about insulation. People think they have a general knowledge of how it works, but how much do they really know? Why the need to know, anyway? Gary Whittaker has an answer to that question. A long time industry veteran and NITP instructor, he says the reason it’s important is that "in order to understand any technology, and to use it properly, you have to understand the science behind it."

Whittaker, a professional engineer and founder of Whittaker Materials Engineering Associates, LLC, continues by saying, "With insulation, there’s a variety of different types that are used in a number of ways. To understand the proper and appropriate way to use it, it’s important to understand the fundamental science and understand the strengths and weaknesses of each insulation type."

It’s a concept that Allen Beck, with 20 years in the industry, won’t dispute. Beck, who works in technical sales for Pacor, Inc., says, "Insulation science is the basic premise for all the products and how they work, whether you’re installing it or manufacturing it or you’re fabricating it. It’s important to know the reasons and why this product is used the way it is."

Learning about insulation science, he says, "Gave me a scientific explanation to the mystery of why and how insulation works. The three basic means of heat transfer [conduction, convection and radiation] were discussed, as well as the interrelationships of R, K, C and U factors. We we’re taught how to use these factors in determining insulation efficiency and appropriate thickness. It actually gives somebody a leg up as far as giving them an idea before they get started about where they need to go, and what type of insulation works best for a particular purpose. It also keeps us informed as far as the accuracy of the program, especially with the 3E Plus® program, where they can tie a lot of these factors into account that weren’t before, such as ambient temperatures or air movement."

Jeff Byers, national specifications manager for Owens Corning, is another industry veteran, with 17 years experience. So he believes he knows a thing or two about insulation. However, even he agreed that’s it not a bad idea to brush up on the fundamentals.

"Without a basic understanding of the science of how insulation and insulation systems work, it’s difficult to determine the actual needs out in the field, and how different applications have different needs," Byers says.

Byers also said that if you learned most of what you know about insulation years ago, it’s important to realize that the industry has evolved. And what might have been commonly accepted ideas at a certain time might not apply today.

"There’s been quite a bit of change in the insulation business with the products that are used," Byers says. "And the quality of the products have changed. The performances have improved. For a business that people don’t think of as one that changes much, there’s been a lot of changes in the products that are used and are available."

At the other end of the experience spectrum is Barry Allen of BWI Distribution. Allen has less than two years in the industry, and admits he had no prior knowledge about industrial insulation prior to assuming his current job.

"I think it [insulation science] is extremely important, especially as kind of a new guy," he says. "It takes insulation from being a commodity type situation to more of a value add if you know more about it and the science behind it. You can present more to a customer. Learning about the science helps because it allowed me to understand a little bit more about applications, a little bit more about why someone would use one product versus another, and what the returns would be for using different thicknesses of insulation."

Jake Carrigan, northeast specification manager for Certain Teed Corp., has a bit more experience than Allen-three years-though his previous encounters with insulation primarily dealt with the standard fiberglass material that’s installed in homes. (He had a landscaping business prior to joining Certain Teed.)

He adds, "In my particular dealings and selling of insulation, it’s not something that I typically have to talk to my customer base about, but I think it helped me develop my understanding of how it works. I have definitely used it some since, mostly talking with engineers. I guess I knew some of it at one point but really didn’t think about it until the refresher."

Filling in the Gaps

Whittaker says that knowledge of insulation basics is perhaps not as extensive today for several reasons. A primary factor is that many companies are cutting staff and forcing people to take on added responsibilities. As a result, getting educated in insulation science isn’t as high in the pecking order.

"In a lot of cases there’s nobody to mentor new people who have come along, and they have to learn it on their own," Whittaker says. "And when you’ve got a lot of other things to do, you don’t do that [learn]. In a chemical plant, for instance, there used to be one guy who did nothing but insulation. That doesn’t happen anymore. You’ve got guys who are specifying insulation who have a lot of other things to do, they don’t have a whole lot of background in the technology, and they’re just looking at manufacturers literature, and they have no way of knowing whether that manufacturers literature [is current or not]."

Carrigan says that those comments do have some merit.

"When I started at CertainTeed, our technical manager did a course that reviewed the basics of insulation," he says. "But to be quite honest, if you don’t use it over and over, it’s not something where you remember everything about it."

Whittaker says even the best salespeople in the industry could use a refresher.

"There’s a lack of understanding on the part of users about the pros and cons of individual materials that could be a disadvantage to them in trying to decide [what type of insulation to use]." He says that those in the industry can be of even better value to end-users by maintaining a strong knowledge of basic insulation.

"If they [have] a better understanding of the technology of the science behind their product," they can do a better job, he says.

Beck also thinks it’s important to learn about a variety of different insulation products to gain a better overall understanding of their different properties and capabilities.

"I think it’s more than beneficial [to learn about insulation science]. I think for anybody in sales or marketing or other aspects, it’s important."

Whittaker says he tries to stress that learning insulation science that doesn’t require Einstein-like intelligence. He says that people should realize that "It’s not ‘black magic,’ it’s not something that’s so complicated that you have to be a degreed engineer to understand," he says. "There are some basic fundamental principles that you experience every day that goes into the design and application of insulation. This isn’t such a foreign thing. This isn’t rocket science. This is some pretty basic stuff here and it’s not that hard to understand."

Gaining Confidence

Obviously, getting a feel for insulation science doesn’t automatically qualify you as an expert, but just having a general grasp can be a confidence booster, especially with clients.

"A lot of the customers that I deal with don’t really know much about insulation," Carrigan says. "You sell it and they make money, but other than that, they don’t really care to know a whole lot. But, when they do have specific technical questions, and I can answer them right away, with no hesitation, I think it adds to my credibility. Hopefully they feel a little more comfortable and know they can come to me in the future with other technical questions.

He continues, "It’s great when I can give them an answer right away. And they’re happy, because in my business that’s what often gets you the sale. As long as I can try to educate them, maybe they’ll think twice the next time about insulation. It may not mean anything right away, but if I can just get a couple people to just think about it, hopefully that will help."

Even an "old-timer" such as Byers says that he’s started to approach his work from a new perspective, which he thinks is also adding benefits for his customers.

"It’s helped me by making me look at the whole system, as opposed to just worrying about the insulation part and making sure those are updated," he says "It’s actually made me look at the whole spec in a new light. I’m asking, ‘Is the way they have this system set up going to support the life of this system?’ Is there something that can be included to insure that the system [stays intact]? That’s helped me widen the scope of the way I look at these specifications, and the way I review jobs when I’m doing, say, an insulation energy appraisal, and I’m recommending insulation to help energy loss. I’m actually looking at, ‘Okay, more than just the insulation, we need to look at perhaps addressing the corrosion on this area of the pipe,’ and look at the whole system."

Changing Perceptions

Allen says he has gained an understanding of the value of saving energy, along with an understanding of how to use the tools that help energy. He thinks that if others do the same, the industry can help transform insulation from being what many consider a commodity product to a necessary part of a facility’s energy program and a tremendous value for end-users. He says that if you do your job with that mindset, everyone will benefit.

"If you’re walking around a plant with a plant manager and you see bare pipe, how many people can tell that guy that [he’s] losing this much energy [and quantify it] by not insulating that pipe," Allen says. "Anybody that’s working in a plant that wants to be a hero to their boss, is going to want to go back and say, ‘Hey, it’s going to cost this amount of dollars to insulate, but this is the return we’re going to get.’"

According to Sam Schell, another NITP instructor, understanding the science helps reinforce the point that insulation isn’t a "one-size fits all" material.

"There’s never just one way to put an insulation system together," says Schell, president of SESCO, Inc., a consulting engineering company he founded. "One of the really cool things that I find about insulation is that there isn’t always [one] right answer. There’s always several right answers. Some of them are a little bit better than others. Some are not quite as good for one [application] but better for another. There’s a huge amount of flexibility. And that’s good for customers and good for selling more insulation. It’s a win-win situation."

Whittaker adds, "The bottom line is that insulation just works. It’s a pretty simple product, It’s kind of an install it and forget it kind of item, but it’s a very important product for a lot of reasons."

Finally, Michele Jones, NIA’s executive vice president, says, "Insulation works the very moment it’s installed. It is one of the few technologies where you don’t have to throw a switch to make it work, and it will continue to work like new if properly maintained for the life of the process."

Significant energy consumption is unavoidable in industry. Automakers need energy to construct cars. Electronics firms need it to produce televisions, radios and computers. Appliance manufacturers need it to build refrigerators, stoves and dishwashers. And then you have companies such as Sunoco Inc., which provide the energy that helps all of those manufacturers create the goods that drive our economy. Of course, to produce its own products, Sunoco also needs to use energy.

However, even companies that make energy like to save it. And that’s Mike Sanders’ job. Sanders is energy coordinator for Sunoco Inc.’s Philadelphia Refining Complex. A 25-year veteran of the refining business, Sanders has overall energy responsibility for the Sunoco’s Philadelphia Refining Complex. Together with the Marcus Hook refining complex about ten miles away, the two facilities comprise Sun’s Northeast Refining. They are connected by several pipelines and operate as a single manufacturing unit. Sunoco is the largest fuels refiner and marketer on the East Coast, with its two refineries having a capacity of more than 500,000 barrels per day.

It goes without saying that in an operation of this magnitude, cost containment and energy efficiency are always vital to success, and Sanders is constantly looking for ways to improve the bottom line in energy use.

Recently, a renewed focus on insulation has become an integral part of the facility’s efforts.

Sanders says, "We look at proper insulation on our heat exchangers and piping as a way of reducing fuel use in our furnaces and boilers. It directly correlates. If you’re saving fuel in the furnaces, you’re saving money, your reducing emissions and you’re improving the process. It’s just a win-win-win. It’s pretty straightforward. You’re reducing incremental Btu’s required from your plant equipment, and that hits the bottom line."

According to Sanders, nearly $1 million has been invested for insulation as part of Sunoco’s energy program in the past three years. And he says it’s not a one-shot deal.

"At Sunoco, insulation will always remain a critical component of our overall energy program" Sanders says. "It’s easy to do, it’s no risk and nobody’s opposed to it. It will remain part of our program. There was a time, when it wasn’t getting a lot of attention, but now we have stepped up our level of attention. It’s part of the plant and it’s part of the infrastructure."

Discovering Insulation’s Value

Like many others , Sanders had some basic knowledge of insulation and refractory, but admits it wasn’t at the top of his radar screen. That began to change in late 1999, when several of Sanders’ colleagues attended a National Petroleum Refiners Association Manufacturers question and answer session, where they spoke with a DuPont engineered services manager about insulation. They referred him to Sanders, and the following week, the two toured roughly a dozen of the refinery’s operating units over the next two days.

"Boy, did I get an education about insulation," Sanders says. "I guess I was a little bit disappointed in how a good bit of it had deteriorated over time. I had not been in the maintenance department for 15 years. During that time we had probably pulled back on some of our spending on insulation, so the integrity and the extent of our insulation had diminished. It was nice to be able to work with the people at DuPont to really show me in detail what they were talking about. I wasn’t qualified to be able to go out and explain the value or the condition level of insulation."

Sanders’ interest in insulation began to increase. He had just become involved with Steam Best Practices (SBP) though the Department of Energy (DOE), and started having discussions with representatives at DOE and the National Insulation Association.

"What we did was sit down and look at our own insulation standards and specs," he says. "We saw that they were rather inadequate. So we decided to embark on trying to improve those, not only to improve them but get people to work using the standards as a guide."

The DuPont representatives showed Sanders several areas that needed some significant improvement because they said that the insulation hadn’t been properly installed, and it had a very slim chance of still being there two or three years down the road. This revelation didn’t please Sanders.

"That bothered me," he says. "Considering the kind of money we were spending to get that work done, it should hold up." Sanders knew that management had some concerns as well.

"What I found was that nobody is opposed to insulation," he says with a laugh. "It’s just where the priority is placed on it. The operations managers that I deal with on an almost a daily basis were all very supportive of improving the insulation and doing more of it, but they also had some concerns about how well things were insulated and why it wasn’t holding up."

Getting Bang for the Buck

To find ways to increase the effectiveness of the insulation program at Northeast Refining, Sanders contracted DuPont to do three insulation surveys as part of a continuing improvement process.

"We determined that by doing ongoing insulation surveys, we developed a Best Practice," he says. "You initiate a long-term program-five, seven years-so if we have 25 process units in our refinery here in Philadelphia, each one would be surveyed every three to four years. That may be overly idealistic, but we envisioned it as a Best Practice to have ongoing surveys followed up by the execution of the work that was identified."

Sanders adds, "We have a finite amount of money to spend on insulation and other areas of our business-we want to get the best bang for out buck. We may decide conscientiously not to insulate some equipment. But we want to get the stuff that has the biggest bang. We envisioned it as a best practice to do surveys through all of our plants on an ongoing basis."

Unfortunately, DuPont decided after about a year and a half that they were going to cut back on their insulation program. Luckily, Sanders was able to secure a back-up plan by securing the services of Win Irwin, president of Irwin Services and a veteran of more than 40 years in the insulation industry. Irwin was able to step in and continue the insulation surveys, and he has four additional surveys scheduled for the 2003 first quarter alone. Sanders is certainly appreciative of Irwin’s expertise.

"We’re happy to have Mr. Irwin working diligently at our facilities to insure that it’s done correctly and that we are insulating all of the proper things in a very cost-effective manner."

Sanders explained some of the strategy and goals for producing successful and informative surveys.

"Refineries are a group of individual process units," he says. "What we try to do is surveys on a unit by unit basis, instead of biting off more than we can chew. I believe in two things; you have to get strong support from the owners of the plant (operations manager, business manager of that facility or unit) and ‘nothing works like success.’ If he or she supports what you’re trying to do, you’ll be successful. They will work with you to get it accomplished."

Sanders continues, "In that regard, we first approached many of our largest units first-obviously because they exhibited the greatest potential for savings, the crude units and cat crackers (fluid catalytic cracking units, which produce gasoline) are our highest energy consumers. I knew that I had support from those operations superintendents in what we were doing. We went after them and did the initial surveys on the crude units throughout Sunoco and the cat crackers, which typically operate above 1,200 degrees (F). So that’s where we focused early on, and I was fortunate that we had good area managers on those units, who want to make it better."

The support that Sanders enjoyed from the facility managers while conducting the surveys continued when he approached upper management for funding.

"At Sunoco, we perform a three-step economic analysis of all projects as to how they contribute to our overall goals of safe, reliable, and environmentally responsible performance," he says. "Insulation projects are ‘no-brainers’ to us as they meet all of those criteria. These are also ‘no-risk’ projects, which benefit the process as well as the people, so, getting support for our insulation efforts wasn’t a problem at all. We presented some of the early assessment reports to our executive management and had an approval to proceed in a matter of minutes."

Convincing Skeptics

Still, how do you convince skeptics that insulation can be an effective part of an energy savings program?

According to Sanders, "I think that’s accomplished on several different fronts. One is to prove to people right away that insulation projects are extremely low risk and very attractive return on investment type projects."

He also points out, "From the standpoint of your own plant personnel, we push it from a number of different fronts. Obviously, there are the energy savings. And all of our area managers have energy targets, so they’re looking at any and all help they can get to reach their energy targets. Then, there’s improvements to the process that happen and you may or may not be aware of them because the lines or heat exchangers are now properly insulated, or perhaps the furnace isn’t leaking tramped air into it. There are just subtle improvements to the process that we’re all striving to achieve. Last but not least, is the inherent safety aspects, which should never be understated."

Sanders also says people should take the time-or make the time-to understand insulation.

"My opinion is that items like insulation and refractory are so poorly understood, and that people just think that they’re too busy too learn its value-such as what types of material work in certain applications and what doesn’t," he says. "I’m currently pursuing some opportunities in better refractory materials and I’m finding it’s fascinating. For instance; how can we do online repairs of heater refractory and boiler refractory and that sort of stuff? It’s pretty interesting when you start digging deep into it."

Along with his interest in refractory, Sanders says he tries to stay on top of other news and trends that may benefit his company. He’s continued to work with NIA, along with the DOE Steam Best Practices and its Office of Industrial Technology to learn more about what’s going on within industry as far as energy efficiency and emissions.

"These two groups are a tremendous resource to those of us in industry and the institutional areas who don’t have the time to ‘re-invent the wheel’ every time we face a problem," Sanders says.

He also makes it a point to give credit for a job well done. "When I see some insulators who have done a pretty nice job, I’ll go over and tell them what a nice job it is," Sanders says. "It’s kind of amazing the reaction you out of people when they’re told that they are appreciated. And I recognize that we have some insulators who have done some incredibly good work."

Sanders concludes, saying, "For too many years, good insulation practices have been overlooked throughout industry in general, and the refining industry was no different than any other. Now people realize that insulation is important to all of us. It’s not something that we should just take for granted. I think some of the best compliments we have received, to date, have come from our own employees and the contractors who realize that somebody cares about the facility."

In my experience, many people who get involved in insulation simply want to grab a box of insulation off the truck, rip it open and start installing it. Few people actually spend much time thinking about the design of the system and the appropriateness of the insulation for the service in which it’s going to be installed. And, it is rarer to find any forethought given to maintenance of the insulation at the time the material is selected and installed.

What most of us don’t realize is there’s a little bit of science that goes into selecting the right insulation material and installing it properly. It means that you have to be part meteorologist, part engineer and part scientist to understand the important factors in selecting the right material for the job. You don’t have to be an expert, but you have to understand some very basic principles about thermodynamics, physics, weather and the properties of insulation materials and how they’re used in various services and environments. Understanding these basic elements ensure an appropriate system is selected and installed for long life and lowest total cost of ownership.

Understanding Fundamental Thermodynamics

Insulation science begins with an understanding of fundamental thermodynamics. It’s a word that sounds scary but it really isn’t. Thermodynamics answers some key questions: what is heat; how do we measure it; how does it flow; and in the presence of heat energy, how can we determine the effectiveness of any material resisting the flow.

We talk about insulation in terms of heat, hot and cold systems, but in reality we’re talking about thermal energy. Heat is a form of energy that is the result of molecular motion. Everything contains thermal energy in varying amounts. Thermal energy subscribes to the laws of physics and like other forms of energy, thermal energy is always seeking equilibrium. That simply means when one object is warmer than another, heat will always try to flow from the object with more heat energy to the object with less, until they have the same amount-equilibrium.

Heat or thermal energy is measured in Btu’s, which stand for British Thermal Units. One Btu is the amount of energy needed to raise the temperature of one pound of water by one degree Fahrenheit. It’s approximately the amount of energy given off when you burn a match.

The basic premise of insulation is that it’s a material that serves as a barrier or retarder to the flow of heat energy. For selecting insulation, you have to know how heat flows and how insulation retards that flow.

Heat Flows

The flow of heat from one object to another is called heat transfer. There are three fundamental methods of heat transfer that must be considered when designing insulation: conduction, convection and radiation.

Conduction

Conduction occurs when two objects are in direct contact with each other. The objects transfer heat by interaction of their molecules. By contact with another object, energy is transferred until it establishes equilibrium between the two objects. For example, if you heat one end of a piece of metal you may not be able to hold on to the other end as it heats up by conduction. This is why we have oven mitts in the kitchen.

Convection

Convection is the transfer of heat energy by movement of a gas or fluid, such as air or liquid. For example, when air is heated it expands, becomes less dense and moves upward. Cooler, denser air moves in a downward direction. This is why the second floor of a house or building is usually warmer. Convection is an issue when we have air flow around an insulation system.

Radiation

Radiation occurs when heat energy passes from one object to another that aren’t in contact without warming the space in between. The biggest source of radiation energy is the sun. Thermal energy from the sun passes through millions of miles of outer space without warming that space until it strikes an object, such as the earth. Radiant heat can be reflected by a white or light colored surface or absorbed through a dark surface significantly raising the temperature. This is why we buy so many white cars in Texas, to keep the car cooler in the summer. We measure the ability of an object to reflect or radiate energy by comparing it to a black body at the same temperature. We call this emissivity.

Climate and Weather Factors on Insulation

Climate and weather factors boil down to water in its three forms, solid (ice), liquid and vapor, ambient temperature of the surrounding air, air movement or wind and radiant heat loading. To get an idea of why it’s important to factor weather and climate when selecting insulation, I’ll share a few stories.

Several years ago, I worked on a project at a Norwegian refinery. A typical refinery has a major shutdown and turnaround every three or four years, depending on their need to maintain their equipment. This particular refinery went through its scheduled turnaround in 1986. When they tried to restart the process, they weren’t able to do so because they had a tremendous amount of corrosion of piping and vessels underneath the insulation. The corrosion was caused by moisture under or in the insulation.

On the west coast of Norway, it typically rains 210 days a year (30-year average). The first year I was there it rained 310 days; essentially there was precipitation during part of every day. The west coast of Norway is warmed by the Gulf Stream as it swings around Ireland and Great Britain, turns east and then hits Norway. Along the coast it doesn’t get as cold as many might think, even though it’s near the Arctic Circle. The climate is Seattle-like, with mostly rain and some snow.

The refinery used a fibrous pipe insulation, which was manufactured with a water repellant added to the binder that holds the fibers together. I have seen a block of the insulation float in water. This would seem a good system for a wet environment.

So, what went wrong? Because we are dealing with a large processing plant with many insulated surfaces in different services, there is no one answer. Let’s consider some of the possible suspects.

New insulation was stored outside unprotected and installed in the rain. The belief was even if the insulation got wet, which it shouldn’t because of the repellant, the system would dry out once it got above the boiling point of water. Most of the time, this happens. The jacketing over the typical hot system insulation isn’t designed to be a vapor retarder. Therefore, moisture vapor can come and go. In fact, various tests show that the time for the moisture to escape can be relatively quick depending on the amount of moisture present, the surface temperature, the tightness of the system, the orientation of the insulated surface and the ambient temperature and humidity. A system continuously above the boiling point of water can dry out as quick as 32 hours or, on a tight system, take several months to never.

Also, the jacketing was placed over the insulation in rainy weather. While the insulation itself may have been repelling water, moisture was trapped in the system. Some was trapped under the insulation and some under the jacketing. As the insulated surface heats up above the boiling point of water, the trapped moisture vaporizes and the vapors move towards the cooler jacketing where the vapor pressure is lower. The water repellant property of the insulation could trap the moisture under the insulation and force the vapor to seek joints and other areas of "less resistance" to escape as the heat increases.

The maintenance manager at chemical plant in Wilmington, N.C., took calcium silicate, soaked it in water for 24 hours, installed 6 feet of the wet insulation on a hot system, capped the ends and covered it tightly with aluminum jacketing. A year later he came back, removed the jacketing and found the insulation still wet.

Another factor to consider was that not all insulated surfaces operated above the boiling point of water. Steam condensate returns are insulated primarily to keep them from freezing and for personal protection. Moisture under this insulation never reaches the boiling point; therefore, gravity and an exit point are the only way out. The most extensive corrosion at the refinery occurred on these types of systems.

In addition, some of the units were down for extended periods, giving any moisture present a prolonged opportunity to create a corrosion cell. This was aggravated by poorly maintained insulation covering that had been breached by mechanical damage. These openings allowed additional moisture in even while the systems were running.

Regardless of how quickly the insulation dries out, moisture was against the insulated steel piping, equipment and vessels while the systems were cold. Water in all of its form is a major enemy.

In the end, the Norwegian refinery was down 42 extra days, and spent in the neighborhood of $20 million to $30 million dollars on overtime, repairing corroded pipes and putting the plant back in a "like new" condition. Add to that the cost of lost production. Installing the right insulation properly and maintaining it is cheap!

You Can’t Fight Moisture Vapor and Gravity

A large chemical company in the Houston area had deep corrugated galvanized jacketing on two 12-foot foot diameter by 90-feet bullet tanks. The deep corrugation on the jacketing ran parallel to the ground, horizontally. Rain falling on the jacketing would run along the corrugation channels until it found an opening to pour through. Over time, as punctures in and deterioration of the jacketing occurred, even more water entered the insulation. There were inspection ports in the belly of the tank. When we pulled the rubber inspections plugs out, water would drain out. Once again, deep corrugation might give strength to a jacketing for a vertical tank and be a good selection for a vertical tank, but on a horizontal tank, the retaining and channeling of water is not a good design.

In another test the maintenance manager at the North Carolina chemical plant took a horizontal section of line insulated with a wicking insulation. Then he took a 10-penny nail, drove a hole in the top of the insulation jacketing and, after a heavy rain, opened it up and found that water migrated 15 feet to 25 feet on either side of the 10-penny nail hole. This shows that it doesn’t take a very large opening in insulation for moisture to get in.

When It’s Chilly Inside

Condensation and process control are the two main reasons for insulating low temperature surfaces. When equipment or piping operates at temperatures below the ambient air temperature, moisture in the air will condense or freeze on the cold surface or, within, or on the insulation.

The moisture vapor in the air outside of the insulation on a cold system is at a higher pressure than the moisture vapor inside the insulation. Following our rule from physics that all forces seek equilibrium, the higher-pressure moisture laden air from outside wants to flow through or around the insulation to reach the lower vapor pressure against the cold surface. Cold systems require special attention because one must design for protection against condensation and consider the affect of moisture vapor transmission.

Water vapor transmission (WVTR) is the rate of water vapor diffusion through a material. The lower the WVTR, the better the vapor retarder.

A chemical plant in Victoria, Texas, had a 40-foot diameter sphere insulated with cellular glass and a vapor retarder. From the outside, for the most part, the insulation looked good. During our inspection we were attracted to the swollen belly of the sphere where we cut a hole in the insulation jacketing. When this was done, about 200 to 300 gallons of water came pouring out, and it continued to drain for several days.

Why did this happen? There are two possibilities-breach of the jacketing/vapor retarder integrity somewhere above allowing direct entry of moisture and/or somewhere in the system, condensation occurred on the surface under the insulation.

People-dropping a tool, walking on the insulation or striking the insulation with scaffolding, piping or other objects-most frequently cause breaches. Occasionally breaches are caused by thermal expansion and contraction, improper installation or wearing out due to age.

Condensation can occur under the insulation for numerous reasons, including breach of the vapor retarder or inadequate thickness. More often, it’s caused by inadequate attention to penetrations. By penetrations, I mean, where a nozzle or structural support member passes through the insulation to connect to the vessel. First, every penetration must be properly sealed to prevent moisture vapor transmission between the object and the insulation. Second, by conduction and trying to reach equilibrium, penetrations are frequently colder than the ambient air temperature, and condensation occurs on the object introducing moisture into the system. Insulation must extend along penetrations far enough to prevent this from occurring.

Once moisture is in or under insulation, gravity causes the moisture to run down to the lowest point. In this case, because the vapor retarder had good integrity down there, it couldn’t let the moisture out. The only clue that there was a problem was the sagging of the insulation under the weight of the water. We calculated that the water weighed approximately 1,800 pounds (or nearly one ton!). This demonstrates that keeping moisture out and condensation from occurring should be a top priority for all cold systems: proper design and installation; good seals; and timely maintenance, are all very critical factors.

Doing Maintenance Properly

It’s one thing when we go into a new construction project and we have no experience with the vessel or pipe that we’re insulating, but it’s another thing to go in and do maintenance. What we teach in the National Insulation Association’s (NIA) National Insulation Training Program about selecting materials for either situation is this: don’t pull out an old specification, dust it off and use it again. Go out, look at the system and make sure that the conditions have not changed. What frequently happens in maintenance (probably 95 percent of the time) is that insulation is repaired with like and kind material. There’s never a root cause of failure analysis done, and so people who have these 12 foot diameter, 90 foot long tanks rip the stuff off, say that this is the kind of jacketing that was on there before, and go put new jacketing on. In essence, they’re putting themselves right back into the same problem.

Weather and Steam Demand

When inspecting industrial facilities, I look at changes in the boiler steam load that occur as the weather changes. Most plants know what their steam demands are. Steam demand in a chemical plant or refinery is fairly uniform. They basically know the factors that influence increased or decreased demand. They have good historical data.

What you can observe is what happens to the steam load when it rains hard. If the steam load goes up suddenly, which it will, that probably represents a number of bare surfaces getting wet and properly insulated and maintained systems cooling down. The rest of it is probably attributable to insulation getting wet. The most important thing in looking at the steam load is how fast the plant recovers. If you notice a rapid recovery once the rain stops, then you have an indication that predominantly bare and properly insulated surfaces got wet. When the rain stopped, they warmed back up and the steam load went down.

But if it takes a prolonged period of time to get back down to normal steam loads-say they regain 20 to 30 percent of the steam that they lost in the first hour and then the next 70 percent takes two days to get back to where they were-chances are they have insulation that’s getting wet. So, looking at steam load can tell you that moisture’s getting into an insulation system if you observe a slow recovery after rain or cold weather. This occurs mostly after rain, because of moisture getting in the insulation. Cold weather will only tell you that there are exposed pipes that are getting cooled off by the weather. It’s important to remember that changes in steam demand are just an indicator, and nothing replaces a through visual inspection by a properly trained inspector.

Mechanical Energy

Those who come from the industrial side of the world, whether it be onshore or offshore, refineries, chemical plants or other industries, know that when operating an industrial system, mechanical forces are introduced into them, either by the flow of the process or by the equipment that moves the product, such as pumps. Those forces create vibrations in the system.

Vibration is a type of mechanical energy that can destroy insulation systems. Understanding the type of vibration and its severity could have an impact on the materials that you select. There have been situations where insulation materials have eroded away from vibration to the point where the metal jacketing was sitting on the top of the pipe, and all the insulation in between was worn out because of the constant movement of the pipe, similar to sandpaper going back and forth. The pipe just kept rubbing away until it wore down to the metal jacketing and bands.

So, there are mechanical forces in the science that transfer energy, or that affect insulation systems, and it’s important to understand those forces.

Hurricane-Proofing

In places such as Texas, when we put in insulation systems, we have to consider what’s the worst type of storm to which it can be exposed. In this setting, it would probably be a hurricane. In a hurricane, sustained winds can be as strong as 150 to 160 miles per hour. So, designing proper securement is a very important part of a good insulation system. In parts of the world where hurricanes and cyclones are common, that needs to be a consideration.

At a chemical plant, in La Porte Texas (near Houston), after a tropical storm, insulation was ripped off some of the columns because they weren’t properly secured. After hurricanes, I have seen pieces of insulation lying on interstate highways. So those forces need to be properly addressed.

Ultraviolet and sun radiation are also issues for insulation, and properly installed and maintained cold systems can prevent the growth of ice, mold and mildew. Additionally, we have to understand the fire resistance properties of different insulations.

The bottom line is that any insulation that’s been manufactured by any of the NIA members is fantastic stuff when it’s properly specified, installed and maintained. It’s essential that we understand the science of insulation so we can pick the right material for the right situation, and then we must treat it with respect when we install it. We have to follow up and to continue to monitor it over time and fix damage early instead of later. It’s amazing to me that people often treat insulation like that old oil filter commercial-the one that says "you can pay me now or you can pay me later." It’s a bad choice to pay later because you’ll always pay a whole lot more. Understanding the science of insulation will save you lots of money.

Figure 1

At industrial facilities, insulation needs to be properly installed, secured and maintained to withstand factors such as elements, mechanical energy and extreme weather conditions.

Figure 2

Indications of weather barrier failure on an insulated tank head.

All the activities of autumn-falling leaves, college and high school football games, Thanksgiving-have passed, and another season-winter-is arriving. With it comes colder weather, Christmas (and Christmas shopping) and the imminent arrival of a new year. Ah, the circle of life continues with great momentum.

So, what does any of this have to do with firestopping? Well, the circle of life for firestopping continues to move forward, affecting life safety in a positive way. In the two years since my last article for Insulation Outlook, many programs have been successfully introduced and are beginning to take hold in the industry. We’ll discuss discuss some of the new developments in testing in these contractor programs and learn how they can help improve life safety while providing innovation to the firestop contracting industry.

Firestop systems have been qualified for use by testing protocol such as ASTM E 814 and Underwriters Laboratories (UL) 1479. Various "hybrids" of the basic firestop qualification test have evolved to meet demands of different and possibly higher movement conditions, in a perimeter wall, such as floor slab gaps, top-of-wall joints and expansion joints. Every test method, however, has one thing in common. They can be tested under UL 1479, and soon, ASTM E 814, at the manufacturers choice, to incorporate an "L" Rating.

L Ratings

What are "L" ratings? They are the ratings that describe "air movement" through firestops, at ambient temperature and at 400 degrees Fahrenheit (F). The test protocol measures the amount of air traveling through a firestop system in cubic feet per minute, per square foot of opening area. The "L" rating is used to establish suitability for use of firestop products in smoke assemblies. UL started testing for smoke in the early 1990s, and, along with the "F" and "T" ratings, began publishing "L" ratings in the UL Fire Resistance Directory.

"L" ratings can be an important part of the total life safety package, when firestopping is used in a fire resistance rated assembly that has both fire and smoke requirements. Model codes have various requirements for smoke passage, depending on occupancy. Although not highly specified at this time, it’s important for the professional firestopping contractor to understand, as its demand is increasing. Where smoke rated construction is required, architect/engineers or code/fire officials may require an "L" rated firestop system. However, not all firestop systems have been tested and listed as "L" rated …so the contractor should beware.

Additionally, there’s a relatively new test method for the exterior skin of the building where it meets the interior floor slab. The intermediate scale multistory test apparatus is used to fire test the slot between the perimeter wall and interior floor slab. Testing has also been developed over the years for "leapfrog" protection. ("Leapfrogging" occurs when fire breaks glass and "leaps" from a lower floor to an upper floor at the exterior of the building.) This is especially true in high-rise construction where full height, floor to ceiling glass is desired by the owner for maximum panoramic view. Perimeter fire protection systems are a highly technical area, where many fire protection, moisture and insulation factors need to be understood to prevent contractor liability. Testing is performed at UL, Northbrook, Ill. and Omega Point Labs, Elmendorf, Texas.

There are a number of dynamic innovations that have taken place in the firestop industry over the past few years. First, here are a few basics. According to best estimates, the firestop products market nationally ranges from about $220 million to $270 million in sales, including mineral wool packing materials used under firestop sealants. Second, growth rates, once as high as 30 percent annually, have been slowing as the market size increases and code changes emphasizing sprinkler protection have been implemented in new projects. The firestop market size growth seems to be "normalizing" at somewhere between 8 percent and 15 percent per year. Third, the contracting portion of firestopping, if a 50/50 average of material to labor is used, is estimated at $250 million. According to contractors around the United States and Canada, more owners and general contractors are awarding firestop installation contracts to a single "specialty firestop contractor," instead of the old "he or she who pokes hole, fills it," which results in more than eight trades installing firestopping.

Firestopping Comes From Variety of Trades

Contractors performing firestopping work come from a variety of trades. At the Firestop Contractors International Association, (FCIA) we’ve seen firestopping contractors come from the mechanical insulation, curtainwall or building insulation, or from the caulking trades, and yet others from trades that saw an opportunity in this area. In the past few years, we’ve even seen firestop contractor members from trades such as roofing, concrete coring, caulking and sealants, along with insulation.

Firestopping is a highly technical piece of the construction industry. To achieve success in this market, Don Sabrsula with Firesafe of Houston, a firestopping and mechanical insulation contractor, states that a "zero tolerance attitude" is needed to accomplish a firestopping project.

"Firestopping is not a ‘close enough for’ construction tolerances trade," says Sabrsula. "If a firm intentionally or unintentionally misapplies firestopping materials, or varies from the tested and listed system design, the firestop system may not work and put life safety in jeopardy."

Alec Rexroat of IMICO, Inc., and executive director of the Illinois Regional Insulation Contractors Association, seconds Sabrsula’s thoughts.

"It took a lot of convincing for field crews to understand this ‘zero tolerance’ mentality," he says. "Until they understood the program, we didn’t let them apply firestop products. These men and women have been working with ‘construction tolerances’ for most of their careers. Once they understood that the firestopping protocol is different, our operations became easier to control. The crews knew that if a variance to the tested system they were given was encountered, [they needed] to find another system in their documentation, or get an engineering judgment through the office to the manufacturer’s fire protection engineer or technical staff. This is probably the biggest challenge a contractor has to deal with in firestopping. But, once the crews, estimators and office staff understand that an unauthorized variance could possibly hurt or kill someone, they fall into step quickly."

Rexroat also mentioned that it’s crucial to have detailed knowledge of the fire wall/floor trades, along with other systems, to understand how firestopping fits into the total fire protection package.

Who Are These Firestopping Guys?

Ken Hercenberg, specifier for RTKL Associates, Baltimore, an architectural firm that performs work worldwide, asked in an opinion column in the Specifier magazine, "Where are the certified Firestoppers?" His opinion was that there should be quantifiable qualifications for a "firestopper." Without these qualifications, "Who knows who the client is getting to install these important life safety products?"

These firestopping guys, or "specialty firestopping contractors," those who focus 25 percent to 50 percent of their time on firestopping, are winning work due to their efficiencies at the "firestop zero tolerance protocol," technical expertise during interviews with architect/engineers and owners/code/fire officials, and because of their overall knowledge of the firestopping trade.

When negotiating for firestopping work, these contractors have a "leg up" on those firms who don’t focus on this highly technical field of work or don’t understand the "zero tolerance" protocol. As more "influencers" of firestop purchases understand the program, the awarding of contracts goes to those most qualified. Please don’t misunderstand, there are firestopping influencers who may not understand the protocol and still buy the "low bid that isn’t based on tested and listed systems." The point here is that the knowledge level of firestopping purchasers, whether it be owners, architect/engineers or general/trade contractors, has increased dramatically since "the old days"….way back in, say, 1995!

Separating Themselves from the Crowd

FCIA worked with Factory Mutual Approvals, a division of FM Global, to develop "FM 4991 – Standard for the approval of Firestop Contractors." This program, an International Standards Organization (ISO) quality type of program, introduces a firm to new concepts in the contracting industry. The ISO writes standards that are world-renowned and have been used by manufacturers to monitor processes during the manufacture of products used in our industry. This program applies some of the same quality process techniques that a manufacturing firm might use.

For instance, manufacturer ISO programs and FM 4991 are similar in that the FM 4991 approved contractor needs to have a quality manual in place. Quality manuals describe what the firm does step by step with a firestop project from estimate to final quality control walkthrough. An FM auditor will arrive at the firestop contracting firm’s office to audit the quality manual interviewing firm personnel to assure that the contractor has the procedures in place to install firestop with "zero tolerance" protocol. FM personnel also visit a project site during this audit to verify that the firm "does as it says it does."

FM 4991 Acceptance

The FM 4991 standard has been well received by architects throughout the country. Architects have been familiar with manufacturer ISO 9000 quality programs for products for years.

"The introduction of a quantifiable quality process for a subcontractor, run by an independent industry leader like FM has had a big impact on acceptance," according to Aedan Gleeson, Gleeson Powers, Inc., FCIA Accreditation Chair. Major firms like RTKL Associates in Baltimore; OWP&P Architects, Chicago, Boston, South Florida and California; M+O+A Architects in Denver …they’ve all begun requiring an FM 4991 approved firestop contractor in their Division 7, Section 07840, firestopping specifications. Additionally, CMD’s "SPECLink," a subscription specification program used nationally, now includes FM 4991 contractors in the specification. FM 4991 approved contractors are listed on the FCIA Web site (www.fcia.org). FM personnel also offer occasional education programs at FCIA industry conferences. These seminars have helped contractors prepare for the rigorous audit that FM Approvals conducts at the firm’s office and jobsite location.

Independent Inspection of Firestops

If so much time is being spent on the installation quality through programs like FM 4991, then why is an independent inspection agency needed to oversee installation even if a professional firestopping contractor installs firestopping?

Over the past few years, firestop industry participants have been frustrated by some firms who don’t take the time to install firestopping properly.

Jess Kray, professional engineer, Kray Cabling, Inc., Richmond, Calif., in an editorial published in The Electrical Distributor magazine, stated, "I see poor or no firestopping all the time. In fact, I have never seen a building that was properly firestopped throughout." When there are many trades trying to install firestopping, anything can happen. Some firms pay attention to the firestop installation protocol while others may not fulfill the obligations that a life safety system deserves.

Currently in our industry, there are four methods of installation for firestopping a project. First, a specialty firestop contractor may be hired by the general contractor (GC) or owner to install the complete scope of work. Second, the GC/owner may split the scope of work to penetrations only and wallops/joints/perimeter fire protection. Third, penetrations might be handled by the trades making the penetration, while perimeter, walltops and joints are installed by a professional firestop specialty firm. Fourth, the GC/owner lets the trades decide how to divide the work. As a result, some trades hire specialty firestopping contractors, while others handle firestopping on their own. On some projects, this decision leads to all trades installing their own firestop scope of work. Conceivably, more than eight different trades could be installing firestopping on a project. This is especially true when "he or she who pokes holes, fills them" is the chosen firestopping method.

This latter "freewheeling" method of purchasing has caused firestopping to become difficult to manage. How can eight trades use only one manufacturer’s tested systems to firestop a building? Such cooperation is difficult at best. Then, if eight product manufacturers are used, will inspection personnel be able to identify which product/system is which during testing? From what industry observers, architects, engineers, code/fire officials, building owners report, this type of procurement method is the most difficult to control. They credit this difficulty to the vast number of trades responsible for firestopping. And, in the event of a subsequent disaster due to poor firestopping, assigning responsibility can be difficult as firms hide behind each other to evade blame.

A situation where multiple trades are responsible for firestopping work is a clear-cut example of why independent inspection should be required. ASTM E 2174, "Standard for the Inspection of Through Penetration Firestop Systems," outlines a protocol for the inspection group to follow when quality control checking a project.

ASTM E 2174 Highlights

ASTM E 2174 outlines the inspection procedure for firestop inspectors to follow. There are quite a few steps in the process. First, a pre-construction meeting is held with the installing contractors to review submittals, details, variances, and the inspection method to be used on the project. Next, mock-ups are built for destructive testing. Then, upon project commencement, the inspector is present to witness 10 percent of the penetration treatment on the project. A final inspection is also performed.

Destructive Testing

The inspector performs destructive testing on 2 percent of the penetrations per 10,000 square feet of floor area, with a minimum of one for each type of penetration. Should there be a 10 percent variance to the installed firestop systems, the inspector will stop checking the project and require that the contractor reinspect their own work. The contractor then notifies the inspector that the work is ready to review again. However, no mention is made in ASTM E 2174 as to who will pay for the extra inspections. Forms are provided in the standard for use by the inspector to assure inspection uniformity across project types and geographical locations worldwide. These forms are submitted daily to the authorizing agency, and filed with the contractor and inspection firm.

Inspector Firm Qualifications

Inspection firms are hired by an "authorizing agency." This could be a building owner, general contractor or code/fire official organization. Qualifications for the inspector are outlined in ASTM E 2174. For instance, the inspector shouldn’t be related to the contractor firm in any way. The inspector can’t be a competitor, supplier, owner, or other related party to the installing contractor. This is to protect obvious biases. For example, if the firm’s competitor who lost the project suddenly became the inspector. Another check and balance is that the inspector should be experienced in this type of work, with references, training records and certifications as proof sources. FCIA is currently working to build an Inspector Firm Approval Program, much like the FM 4991 has for firestopping contractors. The inspector would then have quantifiable certification to review life safety firestop work.

Inspectors can also be qualified by being acceptable to the "Authority Having Jurisdiction." and through implementation of ASTM E 699, a standard for inspector firms, but not specific to firestopping.

Project Close Out

At the end of the work, the inspection firm "closes out" the project. The close out report includes critical information for retention by the building’s future engineering and management personnel. Included in this information are the as built tested system/engineering judgment documentation, any photographic record keeping, field report forms provided from ASTM E 2174 Protocol, and contact information for the installation firm and inspection firm. Additionally, a deviation percentage report is included, along with information about the inspection method used during the project.

Really, Why Have Inspection?

The late W. Edward Demings, renowned management quality advisor to corporations worldwide, states in his many books that design, marketing and service testing are all tied together in a progressive cycle. The cycle, from estimate to final inspection, requires both control from the planning, execution and inspection of finished product, in this case a firestop application. Quality monitoring is a check and balance to assure the purchaser that a process was followed that can result in a successfully assembled product or system.

So, you’re not buying this inspection concept. Well, the argument for deleting inspection might be, "If we’ve hired a qualified, FM 4991 Approved Contractor Firm, why do we need ASTM E 2174 too?" Breck Spain, Performance Contracting, Inc., Phoenix, a large specialty contractor with firestopping capabilities nationwide, states, "Regarding quality and inspection issues, there are some controversies that arise on firestopping projects due to economic reasons such as budget constraints, unexpected cost overruns, mistaken bidding, scheduling and lack of access to work. If a specialty firestop contractor is working for a GC/owner, who requests compromises to a firestop system due to details that may not be correct, (budget or otherwise) the contractor may build the firestop and document that it’s not a system in writing to the owner/general contractor. The inspector, whether independent or fire/code official from the community, is the check and balance that can make sure a true system is installed to protect life safety as he/she is not financially vested in the project, like a contractor on a hard bid project can be …"

Protocol and Engineering Judgments

Firestop contractors, whether FM 4991 approved or not, need to understand the "zero tolerance" installation protocol that must govern this work for life safety. If an annular space in the field doesn’t match up to the tested system drawing provided, the crew at the penetration must either find another tested and listed system in the documentation available, or attain an engineering judgment from the manufacturers’ technical service personnel.

Contractors need to be careful with these "engineering judgments," or "EJ’s." (Also known as "Equivalent Fire Resistance Rated Assemblies" in the FM 4991 Documentation.) The International Firestop Council (IFC), a firestopping manufacturer group, published a position paper on EJ’s. This industry position paper is clear about when a judgment should and shouldn’t be used. IFC’s position is that if a tested and listed system is available from any manufacturer, it should be used before the contractor seeks an EJ. The rationale is that tested and listed systems are proven performers while an EJ is just an opinion submitted for approval by the Authority Having Jurisdiction from the manufacturer’s technical personnel or fire protection engineers. In some areas of the country, architects/engineers and Authorities Having Jurisdiction aren’t allowing EJ’s on projects regardless of what the manufacturer or contractor thinks.

Conforming to this "no EJ" request means more research at bid time for the contractor. Using only tested and listed systems means additional research work on the installing contractor during the project. The architect/engineer, and contractor firm must find a firestopping-manufacturing firm that has a wide availability of tested and listed systems to complete a project without engineering judgments. Ten years ago, this was difficult. Today, the UL Fire Resistance Directory has more than 3,500 tested and listed systems, some with multiple variations, meaning many thousands of available systems.

Drawings Should Be Detailed

Contractors performing firestop work understand the installation protocol. They’ve been trained by the manufacturers, unions, audited by FM, and have invested time and money to perform this work to the "zero tolerance" protocol. However, it seems that the architectural and engineering plans are sometimes not detailed enough to produce a quality firestopping proposal.

To truly affect the industry, architects and engineers need to give the firestopping contractor the firewalls on the mechanical systems.

"It can’t be that hard for the engineer to click on his/her mouse and add the fire walls to the mechanical/electrical/sprinkler drawings making a firestop take off much more efficient and accurate," says IMICO Inc.’s Alec Rexroat. In response, architects say that as projects continue to become more competitive and fees are reduced, there isn’t enough money to cover additional work time in their drawings.

FCIA has been promoting a higher level of contractor quality programs through education about firestopping at its conferences, through work with both Factory Mutual Approvals (FM 4991) and ASTM (ASTM E 2174) and participation in industry forums such as National Fire Protection Association (NFPA), the International Code Council (ICC) and the Construction Specifications Institute (CSI). FCIA membership growth has been strong as more firestopping contractors want important industry recognition. FCIA has included the architectural and code community in its seminars to promote better life safety through the specification of credible, quantifiably tested firestopping contractors.

The market size for firestops is large, and still growing. There have been some threats to the industry, however, through code "tradeoffs" in the International Building Code and NFPA 5000. Trade offs, where firewalls were eliminated due to sprinkler usage, has created concern in the industry about continued opportunities. Manufacturers and contractors alike still believe there’s room for growth in firestopping. We’re still a long way from 100 percent enforcement in firestopping on projects. This enforcement variance ranges from lack of inspection to contractors who may not understand the firestopping "zero tolerance" protocol. Therefore, contractors are still looking to firestopping for good business growth while fulfilling an important life safety service to the community.

This article’s purpose has been to review some new programs in the firestopping and construction industries. The firestop business continues to grow in importance worldwide, as architect/engineers, owners and general contractors realize its importance to life safety. And architects have responded by including both "FM 4991 Approved Contractors" and ASTM E 2174 Inspections" in their Section 07840 specifications.

Watch for more information about other issues in the firestopping industry in this magazine in the future. Until then, "good firestopping to all, and to all a good, firesafe night!"