Word On The Street

• Clinton On IAQ: IE Connections has learned that Hillary Rodham Clinton has been invited to give a welcome address at the Indoor Air 2002 Conference in Monterey, Calif., later this month. While Clinton may not be known among international building sciences people, she is widely known nationally and internationally as a professional, hard-working advocate for children, health, and environmental health, as well as a promoter of health sciences funding. She recently won passage of her “healthy and high performance schools” amendments in the law, Leave No Child Behind Act, making the national case that children need healthy buildings.
  
• New HVACR-IAQ Coalition: A coalition of organizations from the air-conditioning, refrigeration and IAQ communities is coming together to develop training and certification programs for HVAC technicians. Founding members of the AC&R Safety Coalition will include the Refrigeration Service Engineers Society (RSES), the Indoor Air Quality Association (IAQA), and the Education Foundation of the Plumbing, Heating, Cooling Contractors Association (PHCC). Among their first goals will be the development of a series of IAQ educational programs.
  
• Top Priority: EPA Administrator Christine Todd Whitman recently told a group of schoolchildren that she has made school air quality one of her priorities, and she recently visited several schools to publicize her agency's efforts. The agency recently took part in School Building Day, a symposium at the National Building Museum in Washington that featured innovative school facilities practices. Steve Page, director of the Office on Radiation and Indoor Air, was a featured speaker at the symposium.
  
• 1,500 Certified Mold Remediators: The Indoor Air Quality Association awarded credentials to its 1,500th Certified Mold Remediator (CMR) in May, making the non-profit organization the largest trainer and certifier of mold abatement specialists in the world. The total number CMR professionals is 1,509. “The fact that we have pre-qualified, trained, tested and certified more than 1,500 professionals in less than a year is a testament to the credibility and excellence of this program,” said Greg Long, IAQA Certification Committee Chairman.
  
• CT IAQ Bill: Connecticut State Sen. John McKinney, R-Fairfield, recently called upon legislative leaders to address school air quality in the upcoming Special Session. According to Sen. McKinney, the failure to pass legislation to improve the indoor air quality in schools during the regular session was a mistake.

"Letting this bill die was a mistake, plain and simple," said Sen. McKinney. "Fortunately, we have an opportunity to go back and address the issue once again in the special session."

Under the legislation, local school boards would be required to inspect and evaluate their schools' indoor air quality. The measure directs the state Department of Education (SDE), school boards and town building committees to determine how a school building project will affect building air quality before it's approved. It also requires school boards to conduct continuing studies of the maintenance necessary to protect indoor environmental quality.

• Apartment Mold Forum: The National Multi Housing Council (NMHC) will sponsor its annual Technology Conference and four industry Forums Nov. 3-5 in Dallas, Texas. Held concurrently, but independently, at The Fairmont Dallas, NMHC will convene a Mold Forum, a Human Resources Forum, a Risk Management Forum and a Research Forum. Each Forum will combine expert presentations with highly interactive discussions so senior apartment leaders can candidly share information.

  The Mold Forum (Nov. 4-5, 2002) is for senior apartment management professionals, environmental compliance officers and risk managers and will cover:

  • Due diligence
  • Insurance
  • Medical and engineering update
  • Legislative and regulatory developments

  The Forums are open to NMHC members and non-members. Additional information and online registration is available at www.nmhc.org/MeetingRegistration.
  

• Bolden Closing Down: Last month, Kurt Bolden, president of Bolden’ Manufacturing Inc., sent word that the company would be ceasing all operations, including Bolden’s HydroLab, immediately. The company had been producing the Hydro-X, a unit used to provide water drying after floods. Bolden Mfg. will be honoring all warranties on any of their products that are still in use, and Mr. Bolden will be offering the last HydroLab class this month. After that, no more technical information on any products or services will be given out. All those that are currently using Bolden products are encouraged to buy additional units and parts now, as soon they will only be available second hand, and without warranty.
  
• Filtration Articles Online: The National Air Filtration Association has published papers presented at their 2002 Technical Seminar on the association’s website. Download the PDF files free at 
  www.nafahq.org/presentations_2002.htm.
  
• New ISIAQ Project: ISIAQ’s Task Force on Education for healthier buildings will meet at the Indoor Air 2002 meeting in Monterey, Calif., to begin developing a “workbook/textbook” temporarily titled: “Fundamentals of Healthy Buildings for Architects and Construction Managers.” This is an effort intended for graduate level students, with the targeted audience being architects and construction managers. Nadia Boschi will serve as the main chair/editor.
  The proposed framework includes:
  • Course overview including course philosophy, course objectives, and project assignments. Introduction to the subject.
  • Historic perspective.
  • Buildings: Sources and pollutants
  • People: Health effects. Routes of exposures. Symptoms and perceptions.
  • Exposure-Risk assessment, risk perception/acceptability of risk. Factors that cause variability in IAQ problems.

Good IAQ requires the proper operation and maintenance of all HVAC equipment, and knowledge of potential contaminants within this equipment as well as within the facility itself. Inspecting for these potential contaminants should be part of routine maintenance operations. Maintenance personnel should be wary of potential problems with waste disposal, water damage, pesticides, cleaning chemicals, printing and photocopying operations, renovation work, air handling units, cooling towers, industrial operations, kitchens, and bathrooms to name a few. Maintenance personnel should also be familiar with potential problems and inspection protocols.

For instance, personnel should check surfaces inside a cooling tower for presence of biofilm, or to identify the source of an odor correctly. Personnel should be able to disinfect an area with a small amount of mold growth, identify and correct the source of moisture, install and service ventilation equipment, and clean biofilm from AC-unit condensate trays, cooling towers, or sumps. Maintenance personnel should already know the locations of asbestos and lead containing materials, fuel storage and delivery systems, and any other hazardous materials in their building(s) and they should know their responsibilities with regard to those materials.

Ultimately, the maintenance department should have a sense that they are the custodians of the health of the building occupants and this responsibility may require questioning the actions of others. For instance, maintenance personnel should question the practices of a landscaper blowing dirt, exhaust or other contaminants into a building air intake. In addition, they must understand and be trained to react to potential releases of asbestos, lead paint, fiberglass, mold, and any chemicals stored or used in their building.
IAQ-related cleanups pose a general question: when should abatement be conducted by the maintenance department and when should a contractor perform the job?

Asbestos
EPA has several documents that address asbestos regulations and guidelines pertinent to maintenance personnel available from www.epa.gov/opptintr/asbestos/pubs.htm. The main two documents are “Guidance for Controlling Asbestos-Containing Materials in Buildings” (a.k.a. The Purple Book (EPA 560/5-85-024) and “Managing Asbestos in Place” (a.k.a. The Green Book). Secondary texts of significance to building maintenance personnel include: “Interim Guidelines for Maintenance of Asbestos Floor Tiles,” “Asbestos in Buildings: and Guidance for Services and Maintenance Personnel” (a.k.a. The Custodian Brochure).

The Green Book offers building managers more detailed and up-to-date instruction than The Purple Book. The Purple Book is still the EPA’s principal asbestos guidance document, but the Green Book is intended to provide more emphasis on management of ACM rather than removal. The Green Book provides guidance for when an asbestos release can be handled by building maintenance personnel versus contractors.

A major fiber release is generally considered an event where cleanup involves more than three linear feet or three square feet of ACM. A major release generally requires asbestos abatement contractors while a minor release can, under the right circumstances, be remediated by personnel with maintenance worker training and a facility-specific Operation and Maintenance of ACM Program that addresses the cleanup of minor releases. Notably, cleanup of minor releases still requires wetting ACM wastes and disposal in an appropriate leak-tight container (such as a properly labeled, 6-mil thick plastic bag).

State and/or local codes may further regulate activities that involve response to asbestos releases especially with regard to approved disposal facilities. As such they should be consulted and incorporated into the site-specific asbestos O&M program. Regulations that define the extent of operations that can be performed by maintenance personnel and the stipulations for training, personal protective equipment and written programs is addressed by the OSHA substance-specific asbestos standard for construction, 29 CFR 1926.1101. This standard distinguishes four classes of asbestos work and the requirements for conducting work in each of the classes. Building maintenance departments generally restrict themselves to Class IV asbestos work, activities during which employees contact but do not disturb ACM or presumed ACM and activities to clean up dust, waste and debris resulting from Class I-III activities.

Mold
The decision to have the maintenance department or an outside contractor complete IAQ remedial activities is, perhaps, less straight forward when the remediation involves mold growth. Mold has a nearly complete absence of regulations when compared to other building-related hazardous substances like asbestos, radon and lead. However, there is general consensus between a series of documents on prevention and remediation of mold from buildings.

“Mold Remediation in Schools and Commercial Buildings” (available at www.epa.gov/iaq/molds) includes practical guidelines on cleanup that is a consensus of various sources that call for designating small, medium and large remediations based on the amount of surface area covered with mold. Small mold remediations are less than 10 square feet of mold-covered surface area, medium projects have approximately 10 square feet to 100 square feet and large remediations involve areas greater than 100 square feet. Use of full-scale containments similar to those used during asbestos- and lead work are recommended for large projects. Limited or modified Personal Protective Equipment (PPE) and containment are recommended for medium projects and minimum PPE and containment is recommended for small projects.

Recommendations for cleanup methods vary with the type of material affected, such as carpet, cinder block, flooring, upholstery, wood, and wallboard. Decisions to follow recommendations for limited or full containment and use of full PPE are also influenced by the type of mold and the likelihood for exposure and cross-contamination during remedial activities. The sensitivity of occupants who may be exposed during intrusive activities is also a factor in planning the level of containment. For instance, mold abatement in an allergist’s examination room probably requires more emphasis on containment and thoroughness to the cleanup than the same remediation completed in a warehouse.

Training programs provide maintenance personnel with knowledge on the prevention and remediation of mold. There are numerous training programs available. Courses approved by the Indoor Air Quality Association, Inc. provide a curriculum that has been accepted by a panel of IAQ professionals.

Following are some case studies that provide examples of the decision-making process for deciding whether remediations should be completed by the maintenance department or by contractors. The level of training and expertise of the maintenance personnel is a general factor when making these determinations.

Case Study 1
An IAQ investigation was conducted at this federal facility after a bloom of Cladosporium spp. was found covering much of the 500 square foot ceiling in the break room of the building. It was determined that the mold growth was the result of too much air going into the room during the cooling season. Personnel reported that the break room felt like a meat locker during the summer. The problem was corrected by an HVAC balancing contractor.

Since mold contamination in the break room was confined to only the outside portion of the ceiling, and the maintenance personnel at this facility had medical surveillance and clearance to wear a respirator, a decision was made to task the maintenance personnel to remove the mold in the room. Utilizing air purifying respirators with High Efficiency Particulate Absolute (HEPA) cartridges, gloves, disposable coveralls and polyethylene barrier sheets the maintenance crew disinfected the ceiling with a bleach solution. The bleach was brushed and sprayed onto the ceiling. The remediation followed guidelines for large projects as described in the USEPA book “Mold Remediation in Schools and Commercial Buildings.”

The air handling unit at this facility was installed in 1955. Insulation inside the supply chamber had over 107 Cladosporium spp. spores per gram and was badly deteriorated. While the break room represented a far larger surface than the mold contaminated insulation within the HVAC unit, the risk of cross contamination from incorrect clean-up in the HVAC system was greater. Therefore a decision was made to have a contractor following NADCA guidelines perform the remediation. Also, the HVAC/mold contractor was proficient at replacing the insulation with non-fibrous insulation that can readily be wiped clean or vacuumed.

Case Study 2
Another federal facility in Long Island, N.Y., had experienced water overflowing from condensate collection pans on the suspending cooling units prior to my inspection. The drain had apparently clogged because of rust flakes that formed in the condensate pan or coils and entered the drain. The pan was cleaned and sanitized. During the investigation a thin layer of paper dust was found inside the air duct that contained over 106 fungi spores per gram. The duct interior was accessible and easy to isolate; however, the maintenance department was reluctant to perform unfamiliar tasks while working from ladders. As such, this remediation was completed by a contractor.

Case Study 3
A facility in Brooklyn, N.Y., had biofilm residue inside the air ducts that came from overflow in condensate pan that had a clogged drain. The mold and bacteria laden water flowed into the return air duct. The maintenance department unclogged the drain, cleaned and sanitized the condensate collection pan and scrubbed the interior of the duct. In this instance the affected areas of the duct were accessible from a work platform making the task more suitable for the maintenance department.

Case Study 4
Musty odors were observed in an office building at a facility owned by a medical equipment manufacturing company in New Jersey. The odors were observed after the in-line humidifier was left running overnight while the fans inside the AHU were turned off. The maintenance department included full-time HVAC professionals. The source of the odor was traced to rigid foam insulation behind metal panels inside the supply chamber of the AHU. The maintenance department purchased a fogger and treated the AHU including the affected insulation and duct interiors with Bio-Cide brand EnviroCon disinfectant and deodorizer to the satisfaction of the occupants.

Lead Hazards
If building maintenance personnel encounter lead as a potential hazard it is usually from pre-1978 paint. In 1978 the federal government banned the use of lead-based paint (LBP) in homes. However there are no federal standards for LBP in commercial buildings. Individual State agencies should be contacted to ascertain local regulations. Presently, the only guidance for lead promulgated by the EPA is for lead in target housing and child-occupied facilities. EPA is currently working on guidance documents for lead in commercial buildings, public buildings, and steel structures. EPA has found more information is needed to characterize LBP activities in public and commercial buildings. Therefore, it decided to develop a proposed rule on bridges and structures and delay a rule addressing public and commercial buildings until a later date. Commercial and public buildings may have added leeway at present, however, it is advisable to follow inspection, disposal and work practices consistent with information from the National Lead Information Center (NLIC). They can be reached at (800) 424-LEAD to order documents and speak with an information specialist or go to www.epa.gov/lead/nlic.htm.

Building maintenance activities are covered by the OSHA Substance-Specific Construction Standard for Lead, 29 CFR 1926.62. This standard requires exposure monitoring and interim protective measures when personnel engage in the following tasks where lead containing coatings or paint are present: manual demolition, scraping, sanding, heat gun applications, and spray painting with LBP. Stricter protective requirements are required for personnel engaged in abrasive blasting, welding, burning and torch cutting of paint on materials with paint or coatings that contain lead. Paints or coatings that contain at least 0.5 percent lead (5,000 ppm) are considered to contain lead. As such, maintenance personnel are required to conduct air monitoring and provide interim protective measures until the air monitoring results are compared to the OSHA action level. As such, it is generally more practical to utilize a lead abatement contractor to perform any of the tasks listed here on surfaces that contain lead.

Radon
The federal government provides guidance and States enact their own regulations on the testing and remediation of radon. Rules vary from State to State, with New Jersey as the most stringent and notable programs in Colorado, Minnesota, and Virginia. States vary on requirements for firms that provide radon testing, remediations, requirements for testing schools and property transfers, and disclosure of information. Building maintenance personnel can generally perform radon testing and implement remedial programs, however, specific State regulations need to be consulted. Contractors and building inspection firms bring experience and familiarity with testing and abatement methods. The radon remediation systems are specialized systems that need to abate radon from the basement or lowest floor of the building to a location where it cannot re-enter the building or other nearby buildings or occupied areas. In some instances specialized, real-time testing should be accompanied by experienced radon abatement contractors to ensure the extraction equipment is properly located. Guidance documents relevant to building maintenance efforts include the EPA Guidance Documents available from www.epa.gov/iaq/radon/pubs. These include: “Radon Mitigation Standards for Contractors,” “Radon Measurements in Schools,” and “Radon Prevention in the Design and Construction of Schools and other Large Buildings.”

Conclusion
People are inclined to take IAQ for granted until something goes wrong. This attitude is not acceptable for building maintenance professionals. Maintenance personnel should be watchful for issues that could adversely impact building air quality and have a sense for their role regarding intervention. In many instances, maintenance personnel should intervene directly when something is occurring that may have an adverse affect on IAQ, like a truck with an engine left running while the exhaust is being pulled inside. Solutions for preventing contaminants from affecting IAQ include active control of air flow under specific circumstances. This could require providing ventilation with fans when needed or preventing contaminants from entering by closing windows or closing outside air intakes while the contaminants are present. The realm of potential IAQ problems makes it impractical for a maintenance department to have a policy for every problem. On the other hand, regulations and guidance documents addressing building-related hazards like asbestos, mold, lead, and radon require programs designed to ensure knowledge and preparedness for preventing exposure to these agents.

This article looked for consideration of the range of activities involved with providing building occupants with good IAQ. We focused attention on guidelines for deciding when maintenance personnel should perform IAQ remediations and when contractors should be utilized. Naturally important considerations include the size of the maintenance department, the maintenance shop, and the expertise of the individuals in the area of concern.

This article touched on the range of potential IAQ problems and emphasized issues that might require or warrant use of a contractor. A principal text in the IAQ field that addresses potential problems is the 1991 book from the EPA and CDC, “Building Air Quality – A Guide for Building Owners and Facility Managers plus Addendum.” The National Service Center for Environmental Publications maintains and distributes EPA publications in hardcopy, CD-ROM and other multi-media formats. The current publication inventory includes over 7,000 titles. NSCEP also develops and distributes the annual EPA National Publications Catalog. The NSCEP can be visited at www.epa.gov/ncepihom.

Kevin Held is a senior industrial hygienist at BEM Systems Inc., a nationwide, full-service environmental engineering and consulting firm that provides innovative solutions to complex environmental, health, and safety issues facing private industry, state transportation agencies, and federal government clients. You can reach him by calling (908) 598-2600 ext. 194 or by e-mail at kheld@bemsys.com.

IICRC Approves New Carpet Cleaning Standard
by Larry Cooper

The Institute of Inspection, Cleaning and Restoration Certification (IICRC) recently published the Fourth Edition of the Standard and Reference Guide for Professional Carpet Cleaning, IICRC S100. This is the first major revision and update to the document since its introduction in 1991. Included in the revised edition of the Standard is up-to-date information about the importance of vacuuming, maintenance plans and drying. The Standard also includes frequency-cleaning charts for both commercial and residential environments.

The task force for the S100 spent the last two years working on the revision. Hundreds of hours of research and consultation went into the document. Members of the task force included more than 100 companies and individuals in the cleaning and restoration industry, indoor environmental management industry, carpet manufacturing industry, as well as consultants, instructors and other leaders in the carpet cleaning industry.

The IICRC S100 is a procedural document. Professionals throughout the industry use it as the basis for carpet cleaning and carpet maintenance programs. The document is broken into two primary sections. The Standard is the first section. Its distinctive green pages outline step-by-step procedures, which recognize five different methods of cleaning, with variations and combinations of methods.

The second section is the Reference Guide. The reference guide was written to complement and support the Standard. It gives background and technical information about carpet and maintenance programs. Although the material contained within the Reference Guide does not carry the weight of the Standard, the two sections should be considered in conjunction with one another.

The S100 outlines levels of carpet cleaning. The task force members agreed that carpet should be routinely maintained to prevent the buildup of soils. Additionally, carpet manufacturers and fiber producers also recommend that their products be professionally cleaned periodically to reduce the soil buildup to a manageable and healthy state. Several factors to consider when determining the level of cleaning needed include the carpet’s age, condition and maintenance history, along with the type and amount of soil present in the carpet. When a carpet maintenance program for effective soil removal is specified, then the following three levels of cleaning can be combined to care for the carpet: maintenance cleaning, interim cleaning, and restorative cleaning.

Maintenance cleaning is defined as a process used to minimize the impact of soiling and the effects on the carpet appearance. Procedures include placement of walk-off mats, proper cleaning and care of the outdoor hard surface entry areas, consistent regular vacuuming of the carpet and an ongoing program of spot cleaning. Preventative maintenance cleaning extends the use-life of the carpet.

Interim cleaning is defined as surface appearance cleaning. The production rates of interim cleaning are very high, the processes are fast drying and these methods can be used between restorative cleaning. The frequency of interim cleaning depends on the carpet’s location, use and exposure to soiling.

Restorative cleaning is defined as the process of extracting or removing trapped soils and residue from the carpet. These restorative processes use higher moisture levels, lower production rates and slower drying times. The frequency of restorative cleaning depends on the carpet’s location, use and exposure to traffic, soils and the effectiveness of daily maintenance and interim cleaning.

The S100 Standard also describes salvage cleaning. Salvage cleaning is necessary when the carpet’s condition has been severely compromised due to abnormal or abusive soiling or staining, or lack of cleaning. This method can be very aggressive and uses combinations of methods of cleaning and variations in cleaning solutions.

The appearance of the carpet and use-life can be extended with proper care and maintenance. Carpet cleaning frequencies will vary depending on the levels of use, soiling conditions, and proper specification of the carpet product. Homeowners and facility managers must not wait until the carpet looks soiled before beginning a planned program. Significant levels of soil accumulation occur at the base of the carpet fibers long before it becomes visible. In addition, the greater the soiling, the less likelihood of restoring the original color, appearance and texture of the carpet, and the greater the potential of adverse affects of indoor environmental quality (IEQ).

Drying times for carpet cleaning is a very important consideration. The S100 Standard states, “when cleaning carpet, it is highly recommended that drying occur within six to eight hours or less; however, drying time must not exceed 24 hours.” Interim cleaning methods use less moisture and drying time should normally be between 1 to 3 hours. Restorative cleaning methods use higher moisture levels, but the drying time should be within six to eight hours. Speed drying of carpet and assistance using forced air movement will help expedite the drying and shorten the time.

The S100 has two carpet cleaning frequency charts included in the reference guide that are recommendations for maintenance in both the residential setting and the commercial setting. These charts are intended to serve as a guideline for cleaning frequencies. They consider traffic levels, soil ratings, vacuuming and spot cleaning schedules, and professional interim and restorative cleaning.

The Standard recommends that during the process of specification of the carpet that a customized maintenance program or plan be developed using the S100 Standard as the guideline. The program should provide the user with a systematic approach for maintaining the carpet’s appearance at a high level, extending its use-life, and providing for a healthy indoor environment.

Although maintenance programs are often associated with commercial properties, similar programs for residential carpet maintenance are also recommended in the S100. Residential and commercial carpet benefits from scheduled, regular cleaning, especially in high traffic areas of the home and commercial facility.

The S100 Standard, as well as the S300 Upholstery and Fabric Cleaning and S500 Water Damage Restoration Standards, are available from the Institute of Inspection, Cleaning and Restoration Certification (IICRC) headquarters. The cost of the Standard is $35.

The IICRC is the certification registry that develops and monitors educational programs and standards for the inspection, cleaning and restoration industry. Founded in 1972, IICRC is the largest non-profit registry of inspectors, cleaners and restorers serving the U.S., Canada, U.K. and Australia. For more information, call the IICRC at (360) 693-5675 or check the IICRC website at www.iicrc.org.

Larry Cooper is president of Textile Consultants in Denver, Colo. He is also president of Textile Cleaners of America in Arnold, Md. He has been on the IICRC Board of Directors for 18 years and chairs the IICRC Standards Committees. His committees are currently working on updating the S-500 Water Damage Standard and writing a new Mold Remediation Standard. You can reach him by e-mail at textilecon@aol.com.

The tragedy of 9/11 and subsequent bio-terrorism activities have influenced new attention upon the usage of filtration to harden buildings against attacks from airborne environmental sources. In the initial article in this series, the new Methods of Test for filter efficiency and Standards of Care for minimum filtration in the ASHRAE Standard 62 series were discussed as background.

The concern regarding terrorism-provoked incidents is a compelling driver to re-examine the role of filtration in our buildings and homes. Yet, as devastating as such events are likely to be, building owners and operators should consider this new risk in the context of already existing powerful drivers to examine and exploit the full value of enhanced filtration systems in buildings. These conditions pre-date the 9/11 “wake-up call” and have far more wide-spread application than the potential risk of terrorist activity.

Prevailing Reasons To Consider Better Filtration

• Mold infestation in both commercial and residential buildings is now synonymous with IAQ problems, extensive mitigation expense, adverse occupant health effects, and litigation. Though predominantly driven by moisture intrusion factors, enhanced filtration can have an important role in controlling and lowering the concentrations of mold spores in the space after remediation and clean-up. The incidence of mold problems is widespread and growing, and is not limited to the hot and humid coastal climate.
• Industrial chemical spills are much more likely to occur than criminal chemical terrorism. Whether as devastating as Bhopal, or as common as a gasoline or chlorine tank truck accident on an adjacent expressway, these incidents impose a clear and present danger to the environment and surrounding buildings. Thus, nearby plants or even city streets become the possibility/probability of sources from accidental release.
• Acts of vandalism can range from the relatively harmless school children’s pranks with stink bombs to angry workers with intent for revenge and retribution. Such situations are now commonplace occurrences in schools and public buildings.
• Outdoor air pollution is a universal and systemic societal issue. “The solution to pollution is dilution” does not work if the outdoor ventilation air source is pre-polluted, as it is in most U.S. urban areas that routinely exceed the National Ambient Air Standards. Thus, all the air that enters the building or home has an elevated background of particles and chemicals that could be lessened by appropriate filtration selection and application.
• System cleanliness was the original intent of particulate air filtration when it was first introduced in the 1930s to protect central air heating systems from the build-up of flammable fibers from the indoor air. Keeping HVAC systems “clean and dry” is the mantra of most IAQ professionals. Yet, coils, air handlers, and distribution systems are contaminated from the time they are installed, because of the widespread usage of low efficiency “construction filters” and improper or inadequate continuing filter maintenance. Long-term system operation without sufficient filtration has given rise to the need for the relatively recent function of “duct cleaning.”
• Energy cost and BTU consumption are the long-term realities of building efficiency and these costs will remain as primary drivers long after the frenzy of primary drivers long after the frenzy of bio-terrorism subsides. They will require focus on system cost-effectiveness, life-cycle costs, and long-term asset preservation. Filtration fosters energy efficiency by keeping system heat exchange surfaces clean and efficient.
• Indoor air quality problems are the result of contaminated indoor air, whether the contaminants of concern are generated by the occupant’s activities or introduced to the indoor environment by criminal intent. The environmental system must properly cope with particulate and gas phase components of the indoor environment every day 24/7 to provide a sustainable acceptable indoor environment.
• Airborne communicable disease is a continuous threat. Tuberculosis outweighs anthrax when it comes to risk assessment and probability in buildings of assembly. The communication of airborne disease in schools and the workplace is a major contributor to productivity and learning degradation.
• Asthma is widespread and growing at alarming rates particularly in children. This issue is a primary concern of public health agencies—and airborne particulates of less than 2.5 micrometers in size are being scrutinized as contributors. Mold spores, pollen, microbial particles and airborne chemicals are all faulted as contributors to this health effect. Enhanced filtration can also be employed to reduce and control these problem contaminants.
• Productivity is the real cost of unacceptable indoor environments, whether measured by absenteeism in an office environment, or SAT scores in the learning environment. These costs go beyond the health cost and can easily exceed operating costs. Many of the above drivers can be equated to the productivity of the workplace or learning environment.

The remarkable attribute of air cleaning and filtration is that enhanced efficiency can respond to all of these drivers. At the same time, it can attain a heightened level of safety for the occupants in case of a criminal act of terrorism. When all of the related costs and potential savings are included in the value equation, the filtration system becomes an asset with a related return on investment. This is a dramatic shift from the current attitude of filtration as a liability or expense.

Optimizing The Role Of Filter Systems In Building Hardening

The standards publications and development described in the first article in this series along with the sited ASHRAE report on Response to Exceptional Environmental Incidents will provide background on the process of hardening buildings. Collectively, they provide guidance in the selection and usage of filtration. However, the development of hardening strategies for filtration in existing buildings must follow the following matrix of behaviors to set the stage for air cleaning selection.

• Examine the filtration system in the context of an understanding of all of the mechanical systems within the building, how they interface and impact inter-related performance characteristics.
• Understand fully the HVAC system capabilities, constraints, and needs. This includes AHU motor/blower capacity and characteristics, physical constraints, and accessibility.
• Assure that the enhanced filtration strategy links with other planning or modifications involving air balance, building pressurization, envelope tightness, and air capture.
• Fully examine the entire air pathway to understand contaminant sources and pathways of distribution with related pressure differentials that will drive the air throughout and from the building.
• Fully understand the behavior and the delivered performance potential of both particulate and gas phase filters. Don’t assume that filter efficiency is the only consideration for the optimal performance. Include in your filter consideration such issues as capacity and life-cycle behavior issues, airflow and resistance dynamics, and risk assessment and cost effectiveness.
• Before upgrading filtration efficiency, examine and assure that the current filtration system is providing its fullest performance potential.
• As with other building hardening tactics, perform thorough risk and cost analysis to provide acceptable and cost-effective target parameters for system performance.

Getting More From Existing Systems

To attain the maximum performance of existing installed filtration, extreme care should be devoted to ensure air capture by the filter cartridges. By various measurements, relatively small openings around filter retainers, tracks, side-access units and filter cartridge frames can yield high levels of air and contaminant bypass (up to 20 percent bypass reported by some authors). This negates the extraction ability of the filter system. To ensure complete air capture and optimum performance regardless of efficiency:

• Seal between and around installed retainer frames and racks with resilient caulking.
• Install new gasketing in the retainers at the seal plate using resilient polymer gasketing, such as neoprene.
• Gasket and seal slide tracks to ensure that filter cartridge frames impinge and contact at the seal point.
• Properly space, gasket and/or seal between filter cartridges and at plenum access doors.
• Properly support built-up retainer systems with T-bar channels to avoid bank deflection and vibration.
• Apply gaskets between filter cartridge frames in slide-in tracks to seal between vertical surfaces.
• Visually examine entire air handlers for obvious penetrations and leaks of unfiltered air.
• Review maintenance cycles and base change-out scheduling on air resistance rather than inspection or PM cycles.
• Many existing buildings have installed systems that are capable of increased filter efficiency and effectiveness. After making sure that existing systems have appropriate seal and air capture, the following tactics will provide additional efficiency enhancement opportunities. Be cautioned that every building and every system is different, and one size recommendation does not “fit all.” If in doubt about filter selection and application, or its impact upon the system, equipment, or space, employ the expertise of a knowledgeable practitioner (who does not profit from your filter selection).
• Upgrade 1” and 2” filter side access tracks to the highest MERV value available in that size and type of filter. Recent enhanced media versions make it possible to attain MERV 8 to 11 efficiency ranges in 2” pleated filters that will operate with relatively minor pressure-drop premiums. Higher MERV value pleated filters are also available for residential usage.
• In front-loading retainer systems using 2” filters, consider upgrading to higher surface area cartridges of the same MERV value, such as 4” pleats as opposed to 2” pleats. By increasing the surface area alone, efficiency is increased due to lower media velocity, pressure drop is lowered dramatically, and life cycle is extended disproportionately.
• In front-loading retainer systems where higher pressure drop capability and space is available, consider upgrading efficiency to MERV 11-13 by selecting extended media cartridges in depths from 4” to 12” deep in rigid cartridge configuration and up to 36” deep in pocket configuration.
• If appropriate access and room is available, it is possible to upgrade to the higher airflow MERV 13 through 16 minipleat cartridges. The minipleat type filter is a rigid cartridge having high surface area and low pressure-drop properties.
• Evaluate the usage of high-efficiency and high-capacity bypass or standby self- contained filtration systems that can be activated in case of a high concentration incident. Such equipment could be installed as ancillary standby equipment for designated refuge areas, areas of high risk, or for alternate outdoor air pre-treatment.

Enhanced filtration is easiest when air handling equipment is easily accessible; when sufficient space exists in the air stream for filter depth enhancement; when blower capacity will tolerate modest increase in resistance; and/or if space allows for filter bank over-sizing, which results in lower pressure resistance and increased filter life/value. Upgrades to any of the higher MERV filters may require additional pressure-drop and are contingent upon the fan capability and characteristics. Modifications may be required to oversize the filter bank, which lowers velocity and pressure loss.

Benefits From Preparedness And Enhancement Of Filtration

The obvious result from conscientious filtration enhancement is improved building resistance to extraordinary environmental incidents and challenges, but can also yield the following:

• Improved overall building performance
• Improved building efficiency, both energy and operating cost
• Improved and sustained acceptability of building indoor environmental quality
• Reduction of IAQ/environmental complaints and concerns
• Improved building resiliency and sustained asset value
• Improved occupant productivity

H. E. Barney Burroughs is CEO of Building Wellness Consultancy Inc., a consulting firm on filtration and IAQ in Alpharetta, Ga.; past President and Fellow of ASHRAE; chairman of ASHRAE Standing Standard Project Committee (SSPC) 52.2 on Filtration Efficiency; chairman of ARTI (Research Activity of Air Conditioning and Refrigeration Institute) CR-21 IEQ Subcommittee; chairman of AEE CIAQP Certification Board for IAQ Professionals; member of the ASHRAE Presidential Committee on Bio-Terrorism Response. You can reach him by calling (770) 594-1877 or by e-mail at heburroughs@mindspring.com.