Fresh air for asthma sufferers
In August, the National Asthma Education and Prevention Program (NAEPP) issued the first comprehensive update in a decade to the “Guidelines for the Diagnosis and Management of Asthma.” This month’s panel discusses the role of building system engineers in reducing and controlling asthma.
In August, the National Asthma Education and Prevention Program (NAEPP) issued the first comprehensive update in a decade to the “ Guidelines for the Diagnosis and Management of Asthma .” This month’s panel discusses the role of building system engineers in reducing and controlling asthma.
CSE : Describe asthma. Does exposure to poor IAQ lead to increased sensitivity and lower resistance to asthma?
Ouellette : Asthma is an inflammation of the lungs’ airways. The combination of a constriction of the muscles around the ongoing inflammation produces thick mucus. In other words, asthma is a reversible, recurrent, airway obstruction, manifested by coughing, wheezing, and shortness of breath.
Fisk : Many indoor exposures are associated with exacerbation of asthma: tobacco smoke, dust mite allergens, dampness and mold, pet allergens, cockroach allergens, and volatile organic compounds.
CSE : Describe the 10-year process that went into completing this latest update to the NAEPP asthma guidelines.
Brennan : That’s how public health institutions conduct business. The U.S. Environmental Protection Agency (EPA) looks at the health effects of IAQ once every 10 years, but an outbreak needs to happen in order for action to be taken. In other words, a reactive approach is taken rather than a proactive one. For example, early on research showed that the presence of cockroaches in a living environment leads to negative effects on a person’s respiratory system, but action was not taken until the problem reached irreversible proportions.
Ouellette : Traditionally, the treatment for asthma was three-fold: environmental control measures, medications, and allergy shots or desensitization. With advances in medication, environmental control measures and allergy shots were minimized. Consequently, with a heavy reliance on medication, asthma made a comeback in the early 1990s. Instead of treating the source of the problem, we treated the symptoms. Ten years later, there is more emphasis on environmental controls and shots, not in the United States but rather in Scandinavia and northern Europe. In the United States, environmental work has to do with classic allergies, which are only a part of what makes asthma worse. Managed care organizations such as HMOs contribute to the problem by putting restrictions on how much time doctors can spend with each patient. As a work in progress, we are making a turn back to rediscovering the environmental and other sources of asthma.
CSE : How can organizations such as the Natl. Institute of Health (NIH) and the Centers for Disease Control and Prevention in Atlanta increase public awareness about the medical problems connected with poor IAQ?
Streifel : We need to do more environmentally based research. The means and methods are just now in the developmental stage in immunochemistry and the sophistication level has increased over the last five years.
Brennan : Other than the surgeon general putting a warning label on the outside of buildings that do not pass certain IAQ regulations, there is not a lot that can be done.
Ouellette : The problem is that these institutions are taking pieces of the problem and overanalyzing specific aspects, but there are no specialists. There is no interdepartmental communication between organizations such as NIH and Natl. Institute for Occupational Safety and Health (NIOSH), and the result is a splintering of both information and power.
CSE : Why do you suppose there were no professional engineers or field experts on the Expert Panel 3 (EP-3) committee that was convened to update the guidelines?
Brennan : First, the EP-3 Committee is a research group composed of doctors put together by the NAEPP to develop a report that provides a general approach to diagnosing asthma. The four goals of the EP-3 focus on the use of objective measures of lung function to assess the severity of asthma, advance environmental control measures, improve patient education and pharmacologic therapy for long-term management of asthma. In regard to your question, it’s the same reason there are no doctors on the ASHRAE 62.1 or Environmental Health committees. Rarely do medical professionals and building people combine forces in order to produce a case study report. Although the entire advisory board for EP-3 is physicians, there are sections of the guidelines that address structural and building design problems. As a research scientist, I feel there should be more committees where doctors and engineers combine their efforts to produce guidelines.
Streifel : The lack of collaboration between doctors and engineers reflects a misunderstanding of the environment and building science.
Ouellette : The incorporation of building science into building design is essential. In other words, if you take the best-laid plans and put them into a dysfunctional building, the problems will persist. I constantly am asked “Why is it one day we suffer from one thing and not the other?” You have a house full of holes that is ventilating itself and you do not have a heat ventilator bringing in the heat in one spot, and so what you have is a little bit of air coming from different places. Depending on the weather, wind, temperature, and barometric pressure, the variables inside of the house are going to fluctuate, because you don’t have an absolute thermal boundary. If the complete HVAC equation is not taken into account, then building science and biological science will be lacking.
I have been trying to bring doctors and building scientists together for 10 years. I set up programs where I brought in the industrial hygienist. I brought in the American Lung Assn. Health House people. I brought Terry Brennan in as the research scientist. I put a good meeting together, and the doctors wouldn’t show up. I think many physicians fail to realize that there is such a thing as building science, or they do not recognize it as a science. However, there is some progress. NIOSH and other agencies have started learning about the total environmental equation.
CSE : What are some long-term structural changes to HVAC systems in office buildings, that will combat poor IAQ?
Fisk : There are a couple dozen studies showing that air conditioning leads to respiratory and non-respiratory symptoms among office workers. We don’t know why, but if you examine the evidence, more than likely it’s microbial. Air-conditioning systems become contaminated with microbes such as bacteria and fungi, which may be inhaled by building occupants. One preventive measure is to keep air conditioning free of contamination by an HVAC system design that eliminates wetting of duct surfaces by water condenses on cooling coils. Maintenance also is key. Building staff must make sure drain pans actually drain. We speculate that UV radiation of cooling coils, which is effective in reducing mold and bacteria growth, will reduce respiratory symptoms, as was shown in one study.
Streifel : Maintain these systems. Fan coils get full of all kinds of biological material; it becomes aerosolized and transported throughout the building in a very short time. When it dries, it flies. Looking at the infectious disease process in hospitals, there is a short period time when microorganisms are actually in the environment. The tolerance level is not there, but the sensitivity is, among patients with open wounds or otherwise immunosuppressed.
Brennan : Some changes that can be made to HVAC systems are keeping the place dry, clean and pest free. However, mechanical systems and personnel cannot do it all alone. The problem also resides in building enclosure, floor coverings, furnishings, finishes, and other sources as well.
CSE : Do you think that HVAC systems’ design budgets will increase due to the updated guidelines? If so, which specific area of the pre-design of HVAC systems would need a larger budget allotment?
Brennan : More than likely, HVAC system design costs are not going to be allowed to go up. The only way around that is to develop a good building enclosure system.
Streifel : The problem with most HVAC systems is that they are not maintainable. They put them in such tight places that you cannot get in to do the proper filter changes, and they do not put the drains in right. There needs to be an emphasis on proper construction of the air handling system.
Brennan : The most specific area of the pre-design that needs a bigger budget allotment would be the opportunity for engineers and building guys to meet pre-construction and interact with the architect. When the architect is involved, the facility personnel need to be there to ask specific 'what if’ questions. Currently, there usually is no budget allotment for annual simulations that need to be done.
CSE : In an office building HVAC system, what specific allergens affect employees’ respiratory systems and which allergen is the most harmful? What source controls would you recommend?
Streifel : Mold spores affect employees. Moisture management controls, recognition of water stains and damage, and elimination of the source of water damage is essential. The second thing is to make sure that there is enough air moving through the air handling system to keep the air purified. Most people perceive that if we shut down the air handling system, the situation will get better. But that is wrong. All that means is the un-purified air stays in the environment longer.
Fisk : Some of these health effects are allergens such as inflammatory agents. One clear link between allergens and HVAC is filtration. There is evidence of fragments and small particles that are allergenic from outdoor allergen sources. In theory, the more efficient filter systems in the mid-range category reduce our exposure to the outdoor allergens. There has been a lot of research on asthma, most associated with residential buildings. There has been less awareness of the role workplaces and schools play on asthma.
Ouellette : The sick-building syndrome is a result of mold spores. Fiberglass ducts make for transportation highways of dry, warm, and free-flowing air for the allergens. The medical community’s thinking has to evolve in the manner the allergies have. These are no longer classic allergies, and we need to work in conjunction with building designers to fight the source and the symptoms. There are two source controls I would recommend: Use 2008 building science in the construction of new buildings, and do not make the mistake of moving into a building prematurely, before proper medical and structural analysis is complete.
Brennan : Dust mites are the most frequent and thus the most dangerous allergen found in a business setting. Dust mites and mold are the two most potent allergens affecting the U.S. workforce today, followed by paper and mineral fiber circulating in the air. The import of home allergens is also a contributor to poor IAQ. Tobacco smoke, cat dander, and fragrances infiltrate the building on an employee’s clothes and person. The best control is to the keep everything as dry as possible. Have quick-drying rugs in the doorways and an enclosure that keeps the moisture on rainy days out as much as possible. In addition, the places that do not stay dry, such as custodial closets, should be encased, and mold-resistant materials should cover the tiles and certain kinds of fabrics.
CSE : How can an improved IAQ in a school benefit the students medically, and the school’s budget financially?
Fisk : Most of our research shows that schools have less ventilation or outdoor air supply than prescribed in minimum ventilation standards. Higher ventilation rates have been associated with a reduction in absences. The other class of problems prevalent in schools is moisture from water leaks. The financial impact for schools is a two-sided argument. Ventilation systems are major energy expenses for schools. As a result, there are increased energy costs and higher equipment costs for more ventilation. On the other hand, some districts receive funding based on attendance. If the ventilation is higher, more kids will attend school, and the schools will receive money for higher attendance rates.
Ouellette : The advanced age of most schools in the United States means that concrete slabs were used along with brick to build the foundations. The lack of moisture barriers causes a respiratory nightmare. The schools lay dormant all summer, with relatively stagnant air and little vacuuming, and then when school starts up again, the janitors begin to vacuum the carpeted floors. The irritants that piled up on the carpets re-circulate into the air and enter a student’s respiratory system. Disbelief that such a thing is happening is a problem as well. The EPA program, Indoor Air Quality: Tools for Schools, takes a holistic approach to the problem by educating school personnel in practicing the proper structural maintenance. The inhibitor is a lack of a national standard for IAQ levels. The different climates of the country make protocols safe in one area and dangerous in another.
CSE : How does exercise affect asthma and how can school gymnasiums and workout facilities improve IAQ?
Brennan : Allergic reactions occur more frequently when a child or adult is exercising. The worst-case scenario is in school gyms where we find concrete blocks with spaces in the middle, used for acoustic reasons. We find concrete blocks have mineral fibers inside them to reduce noise, but in gyms where children are running around and breathing heavily, the fibers are stirred into the air and they are too small for filtration by the mechanical system. This is a case where building designers and architects need to be on the same page when deciding what materials need to be used. The mechanical side of the problem would be to make sure to keep the gym mats and surrounding areas as dry as possible and as mold-free as possible.
Streifel : We have had situations where swimming pool areas cannot control the moisture and it seeps through the walls, condenses, and creates mold growth throughout the school building.
CSE : What educational programs can help employers spread the word about the dangers of poor IAQ and asthma-related sicknesses?
Brennan : Through the International Facility Management Assn., building operators can save owners as much as $20,000 by having their buildings and stationary engineers pass a building efficiency and job skills certification class. Those who are certified learn skills to run their buildings in a more efficient and eco-friendly manner. The program is offered through the Northeast Energy Efficiency Partnerships.
President,Camroden Assoc., Westmoreland, N.Y.
William Fisk , PE
Head of IndoorEnvironment Dept.,Lawrence Berkeley National Laboratory, Berkeley, Calif.
John Ouellette , MD
Senior Medical Consultant, Moisture Solutions, LLC,Madison, Wis.
Andrew Streifel , MPH
Consultant,EnvironmentalInfection Control Consultants,Chalfont, Pa.