In the days of old, 4 complete air changes per hour were common, just by natural infiltration. Furnaces and air conditioners were naturally oversized to compensate for the higher infiltration rates.
Today's home must, ultimately, be designed and built with the intentions of installing some sort of mechanically induced ventilation system to improve indoor air quality.
Providing better ventilation is certainly a step in the right direction, but it is not a cure-all. We will discuss ventilation more extensively later on.
Right now, let's look at some other types and sources of indoor air pollution.
Most homes have more than just one source of indoor air pollution. Serious risk arises from the cumulative effects from a few to many indoor air pollutants.
Sources and Types of Indoor Air Quality Problems
- Tobacco products - smoking in the home.
- Asbestos containing insulation.
Asbestos
can also be found around and attached to old furnace and duct systems. It was often used to seal duct joints. It can be encapsulated if in good shape, but if deteriorating should be removed by a professional.
- Wet or damp carpet.
- Building components which were treated with formaldehyde.
- Combustion appliances. Any appliance which burns a fuel, if not adjusted and maintained properly can produce carbon monoxide.
Carbon Monoxide
can kill you before you even suspect it's presence in your home!
- Furniture and cabinetry made of some pressed wood products. The glues used in the manufacturing process can add to airborne pollution.
- Humidification systems. Must be adjusted properly to not create high humidity levels condusive to mold and bacterial growth. Must be maintained to ensure no water leaks.
- Household cleaning products - may release volatile organic compounds (VOC's).
- Pesticides.
- Personal care products.
- Hobby products.
- Your central heating and cooling system. Dust, moisture, mold spores, and bacteria can hide in here unseen, and become airborne each time the system blower comes on.
- Pet dander and hair degrades indoor air quality.
- Radon. (see our
radon
page for additional information on this very deadly gas!)
- Molds and mildew in bathrooms and under your kitchen sink.
- Dust mites.
- Fungi.
- Airborne viruses transmitted by people and animals.
- Bacteria carried by people, animals, soil and plant debris.
- Pollens from plants.
- Feces from mice, rats, insects, and cockroaches may become airborne during cleaning procedures.
Somes pollutants are released intermittently by activities of the occupants, such as paints, paint thinners and solvents used during remodeling. Always ventilate these areas well while these chemicals are in use.
The use of cleaning products and pesticides during housecleaning, and smoking indoors, all add to the overall pollution present in a residence.
Some other pollutants in the home are being released continuously from furnishings, building materials, and household products such as timed air fresheners.
High concentrations of air pollutants, without ventilation or air cleaning of some sort, will remain in the air you breathe for long periods of time.
Pollutants can, and will, accumulate to dangerous levels threatening health and comfort, if little or no outside air is introduced into the home.
Therefore, homes which were built tight should be equipped with some mechanical method of introducing outside air into the home.
Also, all homes and their occupants can benefit immensely from good air filtration. All forced-air furnaces or air handlers providing heating or cooling in a residence should have an integral filter. The standard 1" filter is certainly better than nothing, but barely. Today's filtration choices are limitless, and immensely improve indoor air quality. We will investigate some of these air cleaner/purifier choices further on.
Suggested steps (or strategies) for improvement of your home's indoor air quality.
Control the pollutant at it's source.
- Seal, encapsulate, or remove asbestos.
- Clean, vacuum regularly - preferably with non-VOC producing cleaners.
- Have your appliances adjusted properly by a professional.
- Have your air ducts cleaned regularly.
- Open your windows regularly to replace stale indoor air with fresh outdoor air, weather permitting.
- Dust with a damp cloth regularly.
- Wipe down countertops regularly with non-VOC producing anti-bacterial cleaners.
- Wash your bedding at least once per week.
- Do not overwater your houseplants.
- Make your husband help with all this cleaning, unless he's downstairs installing a new ventilation system!
Install a good air cleaner on each of your comfort systems. (Indoor air quality begins with a good air cleaner)
Visit our Air Filtration and Air Cleaner page.
- Media filter
- Electrostatic filter
- Standard electronic air cleaner
- HEPA filtration systems
- Combination air cleaners with multi-stage filters and ultra-violet lights
Install an Energy or a Heat Recovery Ventilator.
Depending on the size of your residence, multiple units may be the ticket.
Read more about Energy and Heat Recovery Ventilators.
- An HRV has an air-to-air heat exchanger for efficiency
- Expels stale air out - fresh air in
- Can be installed on duct system for whole house, or as a stand-alone unit for an area of your home
Install a whole house mechanical ventilation system.
Read more and see ventilation system examples.