ventilation

Improving Indoor Air Quality

There are a number of contaminants and various other factors that contribute to poor indoor air quality. The villains include: common cigarette smoke, asbestos, radon gas, pesticides, insecticides, carbon monoxide plus other oxides, mold and other bacteria. Other factors include building materials used in new or remodeling construction such as: adhesives, caulking, paint, fabrics, and carpeting. Just the simple lack of pure fresh air from "building tight" could be placed at the top of the list.

The result of poor indoor air quality causes headaches, sinus congestion, fatigue or drowsiness, lack of concentration, eye and throat irritations, and even dry itchy skin. Of course, these contaminants and resulting conditions contribute to the "Sick Building Syndrome" we read about frequently. In addition, the dreaded Legionnaires Disease results from lack of proper ventilation or poor IAQ (Indoor Air Quality) as we know it.

A past article from Skyline, the international publication of BOMA (Building Owners and Managers Association) was entitled "Indoor Air Quality: Major Environmental Issue of the ‘90s". (The article concentrates on commercial buildings but comments apply to residential structures as well). The following is verbatim:

"Most indoor air quality experts are in agreement over the historical cause of present-day indoor air quality issues. During the energy crisis of the early to mid 1970s, commercial building owners and property managers generally reduced the volume of outside air introduced into their building in an effort to conserve energy. In some instances, they were required to do so under government regulations. Similarly, buildings designed and constructed in this period were subject to such energy conservation measures. The theory is that these ‘tight’ buildings, combined with the chemical emissions from modern office furniture, equipment, supplies, cleaning solutions and cosmetics, has given rise to present-day potential for indoor air quality complaints from occupants. Additionally, the location of air intakes and exhaust vents may create or compound a problem".

Window applied ventilators such as those manufactured by Titon Inc become a component of mechanical ventilation systems when used. Of course, proper ventilation can be accomplished by mechanical means only through heating, ventilation and air conditioning systems that are typically quite expensive to install and operate. By using either window applied ventilators or through-the-wall units to supply natural ventilation for improved indoor air quality, the mechanical systems become not only more economic to install and operate, but also more efficient.

Where window applied ventilators are incorporated into construction codes such as in Washington State, builders prefer them because of simplicity and reasonable costs. The Washington State Ventilation and Indoor Air Quality Code relating to the need for natural ventilation, reads as follows: "Whole house ventilation systems shall supply outdoor air to all habitable rooms through individual outdoor air inlets, forced-air heating systems, ducting or equivalent means. Doors and operable windows are deemed not to meet the outdoor air supply intake requirements." The Washington State code was mandated in the early 1990s- other states such as Minnesota, Utah, and Oregon have similar references to codes requiring proper ventilation.

The construction industry in the United States is well behind what has transpired in Europe regarding addressing good indoor air quality through window applied ventilators. This concept originated in Scandinavia in the early 1970s. The concept moved across the Continent and is most prevalent in France and the United Kingdom. Japan has recently discovered "trickle" ventilators. Some US and Canadian window manufacturers are incorporating ventilators into windows being exported to Japan and other Pacific Rim countries.

More folks are discovering the need for proper indoor air quality. Using window applied ventilators is an excellent method of introducing fresh air into the indoor environment. Trickle ventilators are unobtrusive, easy to install, and allow very little energy loss. It is evident that indoor air quality issues are here to stay and should be taken seriously.