What's in the air you breathe at home? (part 1 of a 2 part blog)
By John P. Lapotaire, CIEC, MicroShield Environmental Services
Indoor air quality (IAQ) is a hot topic in today's sluggish real estate market. We find ourselves opening the door to a whole new set of challenges each time we view a home that may have been sitting for awhile. Questions race through our minds as we turn the key: "Will this home have that healthy home smell? Will it have a musty stale smell? Did they have pets or smoke?" And finally: "What will I have to do if there is an air quality problem?"
Research has shown that the indoor air quality in our homes can be worse than that of outdoor air. We also know that if a home has been unoccupied, possibly with the A/C off, the air quality will be much, much worse. According to the American Lung Association, indoor air pollution poses a threat to respiratory health and everyone should consider doing what they can to improve the quality of indoor air.
So what can we do to improve the indoor air quality? Is there a way we could clean the house that would actually improve the air quality? There is, and it's not much different than the way you may be cleaning already. But first, you will need to understand a little about indoor air quality and what causes poor indoor air quality in our homes.
So just what is Indoor Air Quality?
- IAQ: Indoor Air Quality refers to the effect of the air inside a home on its occupants.
- GOOD IAQ: The quality of air in a home, which has no unwanted gases or particles in it at concentrations that will adversely affect the occupants.
- POOR IAQ occurs when gasses or particulates are present at an excessive concentration so as to affect the satisfaction or health of the homes occupants.
- Acceptable indoor air is defined by ASHRAE: "Air in which there are no known contaminants at harmful concentrations and which a substantial majority (usually 80%) of the people exposed do not express dissatisfaction." -
- ASHRAE 62-1999
- ASHRA - American Society of Hearing Refrigeration and Air Conditioning Contractors
- ASHRAE 62-1999 Ventilation for Acceptable Indoor Air Quality
- ASHRAE 55-200, Thermal Environmental Conditions for Human Occupancy
An indoor environmental consultant or industrial hygienist can asses your indoor environment and help you identify the source and type of indoor pollutant in your air. Here are the three basic areas of indoor air pollutants according to the Centers for Disease Control and Prevention (CDC), which places air pollutants into three general categories:
- Volatile Organic Compounds (VOC's)
Common indoor air particulates include dirt, dust, fibers, tobacco smoke particles and fireplace or wood stove soot. Airborne particles can range from 0.1 microns in size to 100 microns in size.
Bioaerosols are microorganisms or particles, gases, vapors, or fragments of biological origin (e.g.., alive or released from a living organism) that are in the air. Bioaerosols are everywhere in the environment.
Volatile Organic Compounds (VOC)
Carbon-based chemicals that easily evaporate at room temperature. Some VOC's have odors; other VOC's have none. Odor does not indicate the level of risk. There are thousands of different VOC's produced and used in our daily lives.
Let's drill down a bit. If you take a typical home that is occupied and the A/C is set to a reasonable 74 degrees Faranheit, you should have little or no IAQ issues in the home. If you take the same home and increase the humidity above 60%rh you can have mold growth on furniture and areas of little or no air circulation. The mold growth can then sporolate, which will introduce particulates into the air. The mold can also release mycotoxins into the air which are bioaerosols. If you replace the moldy couch with a new one, you get that new couch smell as the couch off gasses introducing VOC's to the indoor environment.
One house, one issue, all three CDC indoor pollutants introduced into the home. You may be thinking that's not likely to happen, but what I just described is a real case scenario that took place in a home in Central Florida. The fix for this home was to reduce the humidity within the home and collect and remove the excess particulates.
Whether you hire an indoor environmental consultant or you simply want to begin the process of improving your indoor air quality (IAQ), there are a few things you will need to address that will have an immediate impact on the home's indoor air quality.
Continued in Part 2 of "Whats in the air you breath at home?" a reprint of the July 2, 2009 article by John P. Lapotaire, CIEC in the "The Hestia Report."