Indoor air: what you can't see can hurt you?

One of the many beauties of nature is the ability to correct the contamination we place in the environment. The wind blows and dilutes the concentrated contaminates that we discharge through smokestacks. Rains fall and remove gases and aerosols from the air. Plants exchange carbon dioxide for oxygen, and lightning neutralizes many other gases that result in odors. The contaminates that we create, if not naturally removed from the air, must rely on our respiratory system to remove them. Modern airtight buildings that have insufficient ventilation have almost totally isolated interior air space from natures healing environment.

Most of the problems are coming from buildings constructed or renovated in the 70's and 80's, according to a study published in the journal of the AMA. Energy factors were considered into plans for the first time creating sealed off environments. Combine poor air circulation with interior building products that are giving off gases and solvents and you've got a "sick" building.

Any movements or actions that take place affect the air we depend on to support life. Unfortunately, the result in many cases is contamination. Most of us spend the majority of our time indoors (75 to 90 percent) where many of these actions take place. Even the simple act of walking across a carpet creates lint. It originates from the carpet and from the clothes we wear.

When air becomes contaminated gravity pulls the heavier of the pollutants to the ground, while the lighter gases and particles simply drift until they can settle somewhere else. Research proves that 99 percent of airborne particles are invisible. The smallest particle that can be seen with the naked eye is 40 microns. That's rather small when you consider the fact that a human hair is 100 microns in diameter. Tobacco smoke is comprised of particles averaging .25 microns. Ninety-nine percent of all atmospheric dust has a particle size under .5 microns. A wide variety of other indoor air contaminates are less than 1 micron in size, such as common smog oil smoke, carbon black and paint pigments. Harmful bacteria, viruses (TB virus is 0.1 microns) and gases are so small that we can't see them, but they exist in the air we breath. Therefore, what you can't see can hurt you!

The growing awareness of the connection between poor indoor air quality and Sick Building Syndrome makes indoor air quality a vital environmental issue for the 90's and beyond.

Studies show that poor indoor air quality cuts into worker productivity and morale. Common building materials release chemicals and solvents such as formaldehyde, benzene, xylene, toluene and a host of others. They have been proven responsible for respiratory and allergy problems, liver damage and suppression of the immune system.

According to the Environmental Protection Agency indoor air can be 100 times more polluted than outdoor air. The first solution most people think about to solve this problem is to increase the amount of make-up air but it's really not as simple as it seems at first glance. Your air intake might be close to a bus stop, a restaurant exhaust or any number of pollution sources. Also, the more make-up air you use increases energy costs associated with heating or cooling. Even with the best of conditions this cannot be relied upon as a cure all because in the not- so-distant past. the water industry thought that "the solution to pollution was dilution and that train of thought was found to be not a very wise one.

So the question remains as to what the best approach is to combat indoor air pollution and it's result, Sick Building Syndrome. The Audubon Society has taken unique approach in the renovation of their new headquarters. Their state of the art circulation system delivers filtered air at a rate capable of changing interior air six times per hour, double the recommended standard. The system draws in a higher ratio of outside air and moves it all at a high rate of speed to prevent moisture build-up, eliminating a breeding ground for bacteria and fungi. They also selected building materials that do not give off significant amounts of toxic chemicals and solvents. Paints are lead free, water-based latex carpets are formaldehyde free and surfaces of manufactured wood products are sealed with plastic laminate to minimize harmful chemical releases. The icing on the cake was the installation of windows that actually open. Nice touch, but not always a good option in every situation.

This is a good approach for new construction but it would be far beyond the pocketbook of your average building owner or manager to tear out existing interiors and replace everything with environmentally friendly products. The most sensible thing to do first would be to find out if a problem does exist. If you're flooded with complaints from tenants, have the air tested and see if an air quality problem truly does exist. You may have misguided tenants or employees jumping on the bandwagon and there's no reason to spend money that could be used elsewhere.

If tests show the air quality to be less than acceptable you may have to do nothing more than the regular maintenance on the ventilation system that may have been put off for budget or other reasons. I know a gentleman who told me the other day he knows it's time to change the filters when "the air conditioning stops working." That is not a smart maintenance procedure.

A properly maintained ventilation system is the right way to start, but the bottom line is that the filters on your typical air conditioning system were not designed for the efficiency necessary to take out sub-micron particles causing today's problems, and much of the material causing the trouble gets in the system after the.air is brought into the building.

Since contaminated air is re-circulated within a building by the ventilation system, collection of it as close to the source of contamination as possible is necessary to minimize it's effects. In most commercial/office settings this is best accomplished by localized air filtration.

There are several basic types in use today. Perhaps the best known systems are those based upon the Electrostatic Principal s.uch as the well known Smoke Eater. Quite simply, the system works something akin to a magnet and iron filings. They can be quite good at taking out sub-micron particles in low air volumes but lose efficiency as air volume increases. Maintenance requires no replacement filters but regular cleaning of system is time consuming and requires special handling. Electrostatic Precipitators tend to "snap" and "pop" when dirty.

Two other popular methods are media filtration and adsorption. Media filtration is mainly-based on the principal of entrapment. For small particle filtration, HEPA filters are the most efficient, collecting particles down to sub-micron size. Adsorption is where activated carbon is used to remove undesirable odor causing gases from the air we breathe. This technology originated during World War I as a deterrent against war gas.

Today, with the advancement of technology, new techniques have been developed to cleanse the atmosphere we breath. One primary example is Electromedia, a new, patented, self contained commercial air cleaning system. Electromedia, ironically is a by-product of the cigarette industry. It's been rated as the most efficient air cleaning system on the market today.

Every type of system from HVAC to the more advanced filtration systems are only as good as their maintenance record. With Sick Building Syndrome costing the economy an estimated $60 billion a year through worker illness and lost productivity, concern for proper use of and maintenance of these systems should be top priority.

Our modem times have brought us modem problems but by the same token, the technology needed is also here to solve what we have wrought. The important thing is to approach these new situations with sensibility and practicality. Running out and buying equipment you don't need solves nothing. Doing nothing when a problem exists opens doors to all sorts of new troubles. And we're just seeing the beginning.

Water Wise, Inc., and has recently been chosen New York Metro Area Representatives for It's All About Clean Air, Inc., a manufacturer of air cleaning equipment based in Russellville, Kentucky.