Indoor Air Quality

Indoor Air Quality
"Most people are aware that outdoor air pollution can damage their health but may not know that indoor air pollution can also have significant effects. EPA studies of human exposure to air pollutants indicate that indoor air levels of many pollutants may be 2-5 times, and occasion more than 100 times, higher than outdoor levels. These levels of indoor air pollutants are of particular concern because it is estimated that most people spend as much as 90% of their time indoors." (EPA's Air Quality Home Page). Unlike outdoor air, indoor air is recycled again and again. This causes it to trap and build up pollutants. Common pollutants include dust, mold and spores, pollen, pet dander and smoke.
If you are specifically seeking information on mold, visit our new web page specifically devoted to that topic: Understanding and Controlling Mold.

Sick Building Syndrome

"Over the past several decades, our exposure to indoor air pollutants is believed to have increased due to a variety of factors, including the construction of more tightly sealed buildings, reduced ventilation rates to save energy, the use of synthetic building materials and furnishings, and the use of chemically formulated personal care products, pesticides, and household cleaners." (EPA's Air Quality Home Page) The high incidence of indoor air pollution has brought a new phrase into the English language: Sick Building Syndrome. Symptoms include headaches, dizziness, sinus congestion, itchy or watery eyes scratchy throats nausea lethargy, and an inability to concentrate. Sick building syndrome can lead to respiratory infections and can aggravate symptoms associated with allergies and asthma.
The effects of indoor air pollution can be costly in the work place. Symptoms, such as those listed above, may negatively impact the work performance of employees and may lead to increased absenteeism. It has been estimated that contaminated air results in medical costs of about $1 billion dollars a year and costs employers approximately $60 billion a year in employee sick leave and lost production.
The most energy efficient buildings are especially susceptible to sick building syndrome. These facilities are tight: they do not allow indoor air to escape or outdoor air to seep in. Most pollutants are so small (about half the size of a sharp pencil point) that standard throw away air filers trap only 15% of the pollutant particles circulating in the air. As on an airplane, the same air is circulated over and over again and so are the pollutants that air contains. In fact, the particles you see in a beam of afternoon sunlight streaming through window only represent about 1% of the of airborne contaminants, most of which you can't see. Fortunately, indoor air quality can be greatly improved by the use of proper filtration systems, which trap and remove the pollutants that build up in the air, and by the regular maintenance of your building's heating and cooling systems.
See information on Electronic Air Cleaners

Air Filters

All cooling and heating systems utilize some type of filter in their return air vents. However the standard cardboard frame filters used by most consumers are only about 15% effective in removing dust and particles from the air. They have no effect on pollen, micro-organisms, smoke or other similar pollutants.
Electrostatic filters are more effective than standard filters. However, as they get dirty, they quickly become less efficient. To maintain efficiency, they should be hosed off on a regular basis. Because they can be cleaned and reused, they are more economical, in the long run, than the standard throw away filters.
Under the Atmospheric Dust Spot Efficiency test, electrostatic filters rate at 20% efficiency. For marketing purposes, the manufacturers and retailers of electrostatic filters use the "arrestance test" for rating their efficiency. This is a less stringent test than the Atmospheric Dust Spot Efficiency Test and may result in a rating of up to 95% for the electrostatic filter.
Mechanical Air Filters produce the best results. They capture up to 95% of all airborne pollutants, including bacteria, dust, animal hair, dust mites, mildew, lint, fungus, smoke, cooking grease, bacteria and even many viruses. (They rate at 80% - 90% efficiency on the stringent Atmospheric Dust Spot Efficiency Test). These same air pollutants may also compromise your air conditioning equipment by forcing it to work harder, thereby reducing its energy efficiency and possibly its life span. A mechanical air filter can pay for itself by increasing energy efficiency and prolonging the life of your cooling system. Note: the mechanic air filter consists of a case and a HEPA filter. The HEPA filter should be replaced once a year. When consulting an air conditioning contractor about the installation of a mechanical air filter, be sure to ask what his company charges to change out the filter (part plus labor).

Carbon Monoxide - The Silent Killer

If your home uses a gas fueled furnace or gas powered appliances, they must be properly maintained to prevent the release of carbon monoxide. Carbon monoxide is the leading cause of accidental poisoning in the United States. It is colorless, odorless, and tasteless and is virtually impossible for the human senses to detect. In fact, because carbon monoxide is so hard to detect and is so deadly, it has earned the nick-name "The Silent Killer". Most accidental carbon monoxide poisonings occur from house fires, malfunctioning home-heating systems and hot-water heaters. The most common symptoms include headache, nausea, vomiting, dizziness and fatigue.
To reduce the risk of carbon monoxide poisoning inside your home or place of business, have your furnace serviced annually by a licensed technician. An annual check-up should include a thorough inspection of the heating unit for cracks, holes, and leaks which can release carbon monoxide into the air. Custom Air Heating and Air Conditioning performs annual heating check-ups for homes and businesses in north Harris and Montgomery Counties.
While proper maintenance of your gas powered furnace and appliances is your best safeguard against carbon monoxide poisoning inside your home or place of business, you may wish to invest, as well, in a carbon monoxide detector. If you use a detector, be aware that carbon monoxide weighs less than oxygen and can be present in the upper part of a room (close to the ceiling) long before a detector placed on the floor will detect it. A good detector will run between $30 and $80

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