On a daily basis, the average human breathes in about 16,000 quarts of air, each containing about 70,000 visible and invisible particles that are a fraction of the size of a grain of sand. Indoors—where the U.S. Environmental Protection Agency (EPA) says air can be two to five times more polluted than outdoors—people can be exposed to pet dander, pollen, smoke, dust, fumes, bacteria and other micro-organisms.
Poor indoor air quality (IAQ) may be linked to a host of ills. In fact, poor IAQ is so prevalent that the American College of Allergy, Asthma & Immunology notes that 50% of all illnesses are either caused by or aggravated by poor IAQ. It also can lead to absenteeism and reduced productivity in schools and businesses.
Seniors, children and people with compromised immune systems are at particular risk of having health problems linked to poor IAQ. Fortunately, IAQ problems can be significantly reduced with proper air filtration.
In commercial and institutional buildings such as office buildings, schools, hospitals and shopping malls, air filters are part of the building’s Heating, Ventilation and Air-Conditioning (HVAC) System. Large HVAC units—often found on building rooftops—can contain scores of individual air filters, some up to 24 inches thick. In most homes, a single 1-inch thick air filter is a component of the home’s furnace.
While the size and number of air filters differ between home use and commercial building use, the purpose is the same: to capture airborne particles and remove them from the breathing air.
If you believe indoor air quality is a problem where you work, talk to your employer or building manager about upgrading the air filters on their HVAC system. Upgrading from low-efficiency filters to medium- or high-efficiency pleated filters can improve particle removal efficiency (of particles in the 3-10 micron range such as mold spores, household dust, insecticide dust and animal dander) from about 25% to as high as 95%.
At home, make sure you replace old-style panel filters with newer pleated filters. Most panel filters have efficiency values less than 20% for particles in the 3 to 10 micron range. That means that more than 80% of these particles plus virtually all smaller particles pass through the filter without being captured. Look for 1-inch pleated filters, and change filters approximately every three months to ensure continued good performance.
All air filters (whether for home use or commercial building use) should have a MERV (Minimum Efficiency Reporting Value) that indicates the filter’s ability to remove particles of different sizes. A MERV 1 is least efficient at particle removal, while a MERV 16 is most efficient. In most cases, the best filter choice is a MERV 8 pleated filter. However, filters with a higher MERV, such as 11 or 12, may be recommended if there are children, elderly, smokers or asthma/allergy sufferers occupying the building or home.
With most Americans spending an estimated 90% of their time indoors, everyone would be well served to take a closer look at the IAQ implications of air filtration systems.
Ronald Cox, CAFS, is the market manager, Kimberly-Clark Filtration Products. For more information on air filtration and IAQ issues, visit the Resource Center at kcfiltration.com.
