Allergies and Filters: What's the Story?

Posted on in Articles

When you hear the words "air pollution," you probably think of car exhaust and smoke stacks. However, if you’re an indoor allergy sufferer, you know that plenty of indoor allergens constitute air pollution as well. In fact, the EPA has identified indoor air pollution as one of the top five environmental health risks today.

HEPA filters are the key to stopping indoor summer allergies in their tracks. Here’s what you need to know.

What are HEPA filters?

HEPA filters, or high-efficiency particulate air filters, are among the most efficient filters available. The tight mesh they force air to travel through traps minute particles invisible to the naked eye. Examples of pollutants trapped by HEPA filters include dust mites, mold spores, pet dander, pollen and tobacco smoke.

All filters receive a minimum efficiency reporting value (MERV) to indicate the size of particles they can remove from the air. Flat or panel filters that usually come standard in heating and cooling equipment are rated MERV 1 to 4. Pleated or extended surface filters are considered medium-efficiency filters rated between MERV 5 and 13. High-efficiency filters are rated MERV 14 to 16.

Finally, filters rated MERV 17 to 20 fall within the HEPA filter range. These are capable of removing particles down to 0.3 microns at 99.97 to 99.999 percent efficiency.

Where are HEPA filters used?

  • Portable air purifiers: These portable units clean the air in a single room. They come in different sizes to accommodate smaller or larger rooms. A bedroom is the ideal place for an air purifier.
  • Vacuum cleaner: Some bagless vacuums use HEPA filters to trap dust and dust mites as air exits out the exhaust. Some people report that summer allergies are less intense when they use these types of vacuums around the home.

Can HEPA filters be used in HVAC systems?

Your home’s heating, ventilating and air conditioning (HVAC) system should be fitted with one type of air filter or another, and you should be in the habit of changing it regularly. Filters rated MERV 1 to 4 come standard because they remove the largest dust particles that could damage system components without blocking airflow at all.

While you can change this filter out for a medium-efficiency filter rated between MERV 5 and 13, it’s not recommended that you install a HEPA filter in your central heating and air conditioning system. Typical air handlers cannot accommodate such efficient filters because they impede airflow so much. Besides, MERV 5 to 13 filters, especially on the higher end, are nearly as efficient as true HEPA filters. They remove about 80 percent of particles down to 0.3 microns.

However, if your summer allergies are so intense that you wish to enjoy the highest amount of filtration possible, speak with an HVAC contractor about professionally modifying your system. The air handler’s blowing capacity and ductwork size may require modification, and the result will increase your energy bills, but the impeccable filtration could be worth it in some cases.

What techniques can be used alongside HEPA filters to reduce allergies?

By using a HEPA filter in your home, you remove irritating allergens from the air that could make your allergies worse. However, airborne allergens aren't the only type found in your home. Many allergens accumulate on surfaces within your home as well. That means, in addition to using a HEPA filter, you can keep allergies at bay by eliminating allergens at their source. Here’s how:

  • Vacuum frequently to remove dust and dust mites from the carpet. When possible, replace wall-to-wall carpeting with wood, tile or vinyl where it’s impossible for microorganisms to hide.
  • Open the windows at the right times for natural ventilation. Keep an eye on pollen counts and keep your windows tightly shut when they rise.
  • Keep pets outdoors or at least out of your bedroom if you’re allergic.
  • Change bedding frequently. Wash sheets in hot water to kill microorganisms.
  • Wash or vacuum draperies and curtains often. When possible, replace these soft textiles with metal or wooden blinds that you can easily wipe clean.
  • Cover mattresses and pillows in hypoallergenic covers.
  • Dust using an electrostatic cloth to trap dust instead of spreading it around with a feather duster.

Summer allergies won’t get the best of you if you have an action plan in place. To learn more about incorporating HEPA filters into your plan for removing irritating indoor pollution, please contact McWilliams & Son Heating & Air Conditioning today. We proudly offer quality HVAC services to residents in Lufkin and Nacogdoches.