The U.S. Environmental Protection Agency has identified indoor air quality as a significant concern for home and business owners. Indoor pollution impacts occupant comfort, health and productivity. An old adage holds that “the solution to pollution is dilution” and that’s true. But this question remains: What minimum outdoor airflow (OA) rate provides adequate dilution? Of course, the answer depends on the rate of indoor-source pollution and the type of ventilation system used.
Many of us, when we think of air pollution, consider it an ‘outside’ concern, like smog or auto emissions. In reality though, the air in your home, workplace — even your kids’ school — may be full of more pollutants than the air outside. Regular house dust can contain toxins like lead and allergens from pets or even insects. Chemicals used around the house for cleaning, painting or doing routine maintenance can also have a negative effect on the indoor air you breathe. Sometimes pollutants come into your house with new furniture or carpet, or can simply occur naturally like radon or even, in some cases, asbestos.
As we become more urban and the economy has become more based on services and technology, many of us are spending a lot more time indoors, often in hermetically sealed buildings or in houses designed with air-tight efficiency. In the Atlanta metro, where summers can be long and hot, people will often take refuge in a climate-controlled building.
All these factors have increased the focus on indoor air quality; especially as concerns of allergies have escalated. Dust mites, mold of all types and pet dander all manage to find their way into our the air we breathe inside buildings. Dr. David Lang, a preeminent specialist in allergies and immunology, told WebMD that pet dander is practically everywhere — even if you don’t have pets. Lang says that pet dander has “become what we call a community allergen. Pet owners carry it around on their clothes and shed it throughout the day. You can’t get away from it.”
Recognizing the emerging importance of indoor air quality, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) issued its Standard 62 in 1973. Ever since it has been the primary ventilation resource document and contains requirements aimed to: (1) reduce indoor contaminant sources; and (2) prescribe minimum outdoor airflow rates for listed occupancy categories.
The standard addresses indoor contaminant sources with requirements that, for example, reduce the potential for microbial growth, reduce the intake of contaminants from outdoors, and reduce the potential for dirt accumulation within the air-distribution system. Architects are encouraged to select lower-emitting materials, designers will probably include better dehumidification features, and they may specify better air-cleaning devices to remove both indoor- and outdoor-source contaminants.
Children and the elderly, as well as individuals who have asthma or allergies, tend to be particularly sensitive to indoor air pollutants. Long-term exposure to some air pollutants can also have a long-term effect on your health.
Reliable Heating and Air professionals can recommend a solution to most indoor pollutant problems. Often an Aprilaire air cleaner or even a germicidal UV light can go a long way toward improving to keep your indoor air clean and your family healthy.