Many people do not think about indoor air quality or the effect that it has on their health and well-being. While most people understand that air pollution is harmful, most think of only outdoor air pollution. However, since the average American spends about 90 percent of their time indoors, indoor air quality can have a huge impact on your health.
There are three basic strategies to improve indoor air quality
- Removing the Source of the Pollutant
- Improving Ventilation in Your Home
- Indoor Air cleaners
Removing the Source
Eliminating individual sources of pollution or reducing their emissions is the most effective way to improve indoor air quality.
There are simple ways to do this. Sources like asbestos can be sealed or enclosed. Others, like gas stove can be adjusted to decrease the amount of emissions. Source control is the most cost-efficient way to protect your indoor air quality. Another way is increasing ventilation, however this may increase energy costs.
Increasing the amount of outdoor air coming indoors is another approach to lowering the amount of indoor air pollutants in your home.
By simply opening windows and doors, operating window or attic fans when the weather is nice, or running a window air conditioner with the vent control open increases the outdoor ventilation rate. Most home heating and cooling system do not mechanically bring in fresh air into the house, so finding other ways to improve ventilation is a must. Local bathroom or kitchen fans that exhaust outdoors removed contaminants directly from the room where the fan is located and also increases the outdoor air ventilation rate.
The most important time to take these steps are while you are involved in short-term activities that can generate high levels of pollutants. For example, painting a room or stripping paint from the wall, heating your home with kerosene heaters, cooking or engaging in welding, soldering or sanding. Performing these tasks outside when weather permitting may also be the best solution.
Advanced designs of new homes are starting to feature mechanical systems that bring outdoor air into the home. Some of these designs include energy-efficient heat recovery ventilators (also known as air-to-air heat exchangers).
There are many types and sizes of air cleaners on the market, ranging from relatively inexpensive table-top models to sophisticated and expensive whole-house systems. Some air cleaners are highly effective at particle removal, while others, including most table-top models, are much less so. Air cleaners are generally not designed to remove gaseous pollutants.
The effectiveness of an air cleaner depends on how well it collects pollutants from indoor air (expressed as a percentage efficiency rate) and how much air it draws through the cleaning or filtering element (expressed in cubic feet per minute).
A very efficient collector with a low air-circulation rate will not be effective, nor will a cleaner with a high air-circulation rate but a less efficient collector. The long-term performance of any air cleaner depends on maintaining it according to the manufacturer’s directions.
Another important factor in determining the effectiveness of an air cleaner is the strength of the pollutant source. Table-top air cleaners, in particular, may not remove satisfactory amounts of pollutants from strong nearby sources. People with a sensitivity to particular sources may find that air cleaners are helpful only in conjunction with concerted efforts to remove the source.
Over the past few years, there has been some publicity suggesting that houseplants have been shown to reduce levels of some chemicals in laboratory experiments. There is currently no evidence, however, that a reasonable number of houseplants remove significant quantities of pollutants in homes and offices. Indoor houseplants should not be over-watered because overly damp soil may promote the growth of microorganisms which can affect allergic individuals.
At present, EPA does not recommend using air cleaners to reduce levels of radon and its decay products. The effectiveness of these devices is uncertain because they only partially remove the radon decay products and do not diminish the amount of radon entering the home. EPA plans to do additional research on whether air cleaners are, or could become, a reliable means of reducing the health risk from radon.