No two homes have exactly the same indoor air problems. The quality of the air in your home is influenced by how you live – pets, smoking, sources of moisture, cooking and cleaning habits and household equipment. It's also affected by climate, construction materials and the type of home you live in. It's not necessary or even possible to eliminate all contaminants in indoor air, but it is possible to minimize exposure to pollutants and irritants that can cause allergy or asthma symptoms.
Q: Where do indoor pollutants come from?
A: Indoor pollutants come from two sources: things generated inside your home (such as dust mites, mold spores, household pests) and those you bring in from outside (including pollen and particulates from polluted air). Adults inhale approximately 15,000 quarts of air each day, so what's in that air plays a major role in your health.
- Tobacco smoke contains more than 4,000 compounds, many of which are strong airway irritants.
- Cooking, cleaning and redecorating can spread indoor pollutants.
- Most homes generate about 40 pounds of dust per year for every 1,500 square feet of space. About 40,000 dust mites can be found in only one ounce of dust.
Q: What are dust mites?
A: Dust mites are tiny insects that feed on human skin flakes and are found in mattresses, pillows, carpets, upholstered furniture, bedcovers, clothes, stuffed toys and fabric and fabric-covered items. Body parts and feces from dust mites can cause allergy and asthma symptoms in people who are allergic, and exposure to dust mites can cause asthma in children who have not previously exhibited asthma symptoms.
To evict dust mites from your home:
- Cover mattresses and pillows with zippered encasements.
- Wash bedding (sheets, blankets and bedcovers) once per week in hot water (130° F).
- Replace carpets with hard flooring and washable rugs.
- Eliminate other soft furnishings where possible.
- Maintain low indoor humidity, ideally between 40 and 50% relative humidity. Humidity levels can be measured with an instrument called a hygrometer – available at local hardware stores.
Q: How can I get rid of other indoor allergens?
A: To eliminate allergens like mold and insects, your best course of action is to look for the source of the problem first – fix leaky pipes to discourage mold growth, store food in airtight containers to eliminate a free buffet for rodents and pests. Check every nook and cranny of your home – behind the refrigerator and under sinks, inside closets, plus areas around major appliances like washers, water heaters and HVAC systems. AANMA's Indoor AIRepair kit offers clues to identify the source of indoor air quality problems, plus low- and no-cost solutions. Once you eliminate the source, you can clean up allergens and be confident that they won't return.
Q: What is an HVAC system?
A: HVAC stands for "heating, ventilation and air conditioning" – three functions often combined into one system in today's homes. Warmed, cooled or dehumidified air flows through a series of tubes – called ducts – to be distributed to all the rooms of your house.
Q: Can I use my HVAC system to clean my air?
A: Your heating, ventilation and air conditioning system acts as your home's lungs – moving, filtering, warming and cooling the air you breathe each day. You can reduce airborne allergens by making sure your HVAC system is well maintained and installing an extra air-cleaning or filtering system to help reduce allergens and irritants in your air space. The filter that comes with your HVAC system isn't designed to help you breathe better – it just keeps dust and debris from clogging up the working parts of your system.
Q: What type of air cleaner should I use with my HVAC system?
A: The size of your home (be it an apartment, townhouse or single-family home) and your personal health needs will dictate the right system for you. The clean air delivery rate (CADR) of an air cleaner is one factor to consider – the higher the CADR, the more effective the unit will be at cleaning airborne particles and allergens from your home's indoor air. CADRs for residential air cleaners range from 10 to 1,200.
If your home doesn't have a central HVAC system – where conditioned or heated air is circulated through vents throughout the home – you may want to consider portable air cleaners in the rooms you use most often like bedrooms and family rooms. If you do have a central HVAC, a whole-home air cleaner can help keep airborne allergens and irritants out of every room in your house.
Q: How do I find the right air cleaning system for me?
A: A reputable heating and air conditioning contractor can offer expert advice about available whole-house air cleaning systems and the effects you are likely to notice after one is installed. It can be installed during or after your home is built.
When considering a whole-house air cleaner, look for one that will remove the greatest percentage of particles that are small enough to cause asthma and allergy symptoms – anything smaller than 0.5 microns (the size of pet dander and dust mite allergens). Some cleaners can filter particles as small as 0.1 microns (such as skin flakes, bacteria and some viruses). Some whole-house air cleaners can also help reduce the humidity in your house, which will limit mold and dust mite growth.
