Tight Houses = Bad Air

During the energy crisis of the 1970's we did two things to help conserve energy. Unfortunately, these two things have consequences that we didn’t understand at the time. First, we made our houses virtually airtight. Some of you may remember that older-style heaters and air conditioning systems actually took in air from outside and circulated fresh air in the house. They stopped doing that in the 1970's and the standards for an "energy efficient" home actually require houses to be sealed up to prevent outside air from getting in. Second, we began using more exotic insulation and building materials, such as Urea-Formaldehyde Foam, that gave off hazardous gases. While these steps saved energy, they also created a new problem: "Indoor Air Pollution."

Ant's Nest Corrosion?

For the past several years, the inside coils of some air conditioners have started leaking Freon even though the units were just a few years old. The copper pipes the coils are made from developed corrosion and tiny cracks which looked a lot like the ant trails in the old "ant farm" toys. The air conditioning industry undertook several research projects to find out why. This corrosion is caused by organic acids, such as formic acid which is a breakdown product of all of the formaldehyde we now use in new home construction! It's in the glues used to make "engineered lumber," in particle board, chip board, OSB, paints, varnishes, carpeting and even in blinds.

Some air conditioning manufacturers have started coating the copper pipes with tin to help prevent this problem in the future, but I think the problem is not with the copper coils but with the amount of formaldehyde in our indoor air. When we recently moved into our new home, we installed an "Energy Recovery Ventilator" that completely changes the air in the house with fresh outside air 6-12 times a day, reducing the formaldehyde and other gases given off by modern construction materials. This unit has a heat exchanger built in so that it uses the outgoing air to cool or heat the incoming air, depending on the season.

Sick Building Syndrome

Tight construction with little outside air has had other impacts on human health. In the 1980's a new phenomenon called Sick Building Syndrome became an important public health issue. People began to get sick from the building they worked in or the house they lived in. One of the primary causes of Sick Building Syndrome is mold. In humid areas of the country such as Tennessee, indoor mold is a growing health concern, but there are other germs in the air as well. Being constantly exposed to large amounts of  the mold, bacteria and viruses in bad indoor air takes a toll on the immune system. Some researchers believe that indoor air quality problems, primarily from mold, are one reason for the jump in allergy and asthma cases and may even play a role in Chronic Fatigue Syndrome and other health problems.


In with the Good--Out with the Bad

You can immediately improve the air quality in your home by simply opening a window. While you won't want to do that on hot or cold days, on days when the weather allows, let some fresh air in. Use bathroom and kitchen vent fans and be careful about the products you allow in your home. Some are labeled for use with "adequate ventilation" and that really means “outside.” Carpet, paint, wood finishes, plastics, cosmetics and cleaners give off various organic gases that are known to cause health problems. Of all the studies I’ve read on this subject, one in particular hit home. Researchers found that an unusual chemical with the tongue-twisting name of perfluorooctane sulfonate was being discovered in blood samples at hospitals and blood banks. Most of us know this chemical better by its tradename: Scotchgard. In May of 2000, 3M Corp. announced that it was phasing out production of this chemical. It's not known what health effects, if any, Scotchgard causes, but imagine how many other common household chemicals get into our bodies because they have no where else to go.

I've been told to hang freshly dry cleaned clothes in the garage for a few days before bringing them in to the house. There are traces of dry cleaning solvent still in the clothes, and once chemicals get into most houses, they have a hard time getting out. Bird owners are warned not to cook with Teflon because the fumes can be toxic to birds. What about us?

Consider that when you use a spray can of anything, or fingernail polish, furniture wax, bleach or any of dozens of common household chemicals, those chemicals stay in the air in your house for weeks on end.

Improving Your Health and Air Quality

There are several practical steps you can take to improve your home's air quality and your family's health.

Portable air cleaners, even HEPA-types, are useful for removing particles, but have little or no effect on organic chemicals.

Have your Air Conditioner professionally cleaned. Most people are shocked when they see the mold and other gunk that accumulates inside the A/C unit. Cleaning ducts is only part of the job.

Fresh air from the outside is very important. This used to be discouraged because it can cost a lot to heat or cool the outside air before bringing it in, but today there are air-to-air heat exchangers available that let you get fresh air into your home and still save energy. For more information, click here: http://www.hvi.org/benefits/

Another device that is growing in popularity is an Ultraviolet (UV) light system installed inside the air conditioner's duct work. The powerful UV light kills mold spores, bacteria and viruses.

Be aware of the chemicals that you are bringing into your home. Read the labels and follow the warnings.


For More Information about Indoor Air Quality

http://www.epa.gov/iaq/

http://www.epa.gov/iaq/pubs/insidest.html

 



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