Indoor Air Quality and Your Health
Indoor Air Quality (IAQ) is a measurement of how much the air within your home is free of common indoor pollutants, such as tobacco smoke, pollen, dust, dirt, and other airborne particles. Controlling these indoor pollutants improves your IAQ, which can help reduce your risk of health concerns.
To understand what you should know about IAQ, in this post we cover:
- Types of air pollutants
- What causes poor IAQ
- What the effects of poor IAQ are on your health
- How to improve your IAQ
Indoor pollution results from any number of sources, including:
- Tobacco smoke
- Fireplaces, heaters, wood burning stoves and other combustion-based appliances
- Household cleaners
- Deteriorated asbestos insulation
- Volatile Organic Compounds (VOC) such as formaldehyde used in furniture, flooring materials, paints and varnishes
- Biological contaminants that include bacteria, viruses, animal dander, cat saliva, dust mites, and pollen
- Relative high humidity over 70%, conducive to the growth of mold, bacteria, viruses, and dust mites; increased water vapor also facilitates VOC emissions
- Radon and pesticides emitted from soil that enters through cracks in the basement or crawl space areas
- Outdoor air containing fire smoke and other fossil fuel burning byproducts
Just about anything in your house–from pets, to new furniture, to a wood stove, to using glue to make model airplanes, to a kid coming home who caught a cold at school–is a potential source of pollution and poor IAQ. But we don’t consider these a cause of poor IAQ. What causes poor IAQ is poor ventilation. If too little air circulates outdoor air in and indoor air out, pollutants accumulate and IAQ declines.
Modern buildings are designed to prevent outdoor air from penetrating inside, and consequently inside air from getting out, to improve energy efficiency. Ventilation is not an issue when windows are open. But during prime heating and cooling seasons, when houses are air tight, improper and/or inefficient ventilation leads to poor IAQ.
One of the chief problems with poor IAQ is that we are unlikely to notice it. Indoor air pollutants, with the exception of tobacco smoke, are for the most part odorless. So there’s nothing really to alert us of poor IAQ except the onset of symptoms such as runny eyes and coughing, and for those with respiratory issues such as asthma, more frequent attacks. Even then, we are likely to attribute these symptoms to the weather or allergy season.
Your immediate reaction to poor IAQ depends in part on the state of your health and your age. In many cases it depends on individual sensitivity to air pollutants. At the very least, poor IAQ can cause irritation to the eyes, ears, and throat; it can also cause headaches, dizziness, and fatigue. Long-term exposure can potentially result in serious side effects, including respiratory disease or cancer. According to the Occupational Safety and Health Administration (OSHA), “Some specific diseases have been linked to specific air contaminants or indoor environments, like asthma with damp indoor environments. In addition, some exposures, such as asbestos and radon, do not cause immediate symptoms but can lead to cancer after many years.”
Harvard Health Publishing recommends keeping your house as clean as possible with regular vacuuming, cleaning clutter, and regularly washing bedding, drapes, and other items that tend to collect dust. “A clean house may be a healthier house, because good indoor hygiene can greatly cut down on dust and animal dander. Your cleaning efforts should focus on strategies to reduce the accumulation of pet dander, mold, and dust lurking in your home.” Of particular interest is the recommendation to avoid indoor plants, which many people think adds to indoor air quality. But according to Dr. Nicholas BuSaba, associate professor of otolaryngology at Harvard Medical School, “Indoor plants are pretty, but they can also collect and foster the growth of mold. So, if indoor allergens are a problem, you’ll want to avoid them.”
However, the best way to improve IAQ is with better ventilation that circulates air throughout the house from outside in, and inside out. You might be wondering, “Wait, if I’m bringing outside air into my house, and with it, outside air pollutants, aren’t I just making matters worse for IAQ?”
Which is why the very best way to improve IAQ is to filter outside air before it circulates throughout your house.
Your central HVAC (Heating, Ventilation, Air Conditioning) system has an air filter for the specific purpose of removing airborne particulates and improving your IAQ. Not all air filters are the same, however. Some are designed to capture more particulates and remove specific pollutants.
Air filters are rated in efficiency by a standard called MERV (Minimum Efficiency Reporting Value). MERV measures how much matter passes through an air filter, based on a scale of 1 to 20. Higher rated air filters capture smaller-sized particles. The higher the MERV rating, the fewer particles pass through the air filter and circulate throughout your house and, consequently, the better your IAQ.
But don’t go out and get an air filter with the highest rated MERV. Anything higher than a 9 MERV is for industrial, medical and scientific purposes, and is overkill for a home application. In fact, the MERV rating you want depends in part on the design of your HVAC system. A professional HVAC contractor can tell you which is best. A general rule of thumb is that whatever type of air filter comes with your system is the one you should use.
However, in some situations, you could require an air purifier or an upgrade to the filtration system. Many people confuse “air purifier” with “air filter,” but they are not the same. The basic difference is that air filters trap certain dust and dirt particles, while an air purifier uses ionization to remove particles most air filtration systems cannot. If you live in an area with heavy pollution and/or someone in your family has respiratory issues, you may breathe easier with the added protection of an air purification system.
One trick you might consider is installing a thermostat with an “air circulation” mode. This allows you to run the system fan to circulate air at periodic intervals, for example, 15 minutes every hour. More moving air means more air passing through your filter, which means more particles are trapped, improving your IAQ.
What is absolutely critical to maintaining good IAQ is regularly cleaning and/or replacing your air filter. Periodic maintenance of your HVAC system is essential to improve performance and maintain efficiency. It also ensures dirty or malfunctioning air filters don’t actually cause more air pollution, as well as impede system performance.
If you are particularly concerned about IAQ, purchase an AQI monitor. The monitor can help warn you if your indoor air is getting dirtier, in which case you can run the air circulation mode more frequently.
Consult the IAQ Experts—Ongaro and Sons
It’s a good idea to consult a knowledgeable expert about IAQ. Certified technicians can help you assess the IAQ of your home, and help you weigh the pros and cons of different air filtration and ventilation solutions to determine what best fits your home and family needs in order to improve your IAQ.
Installing and maintaining an air filtration system or air purifier requires professional skill and experience. Call the IAQ specialists at Ongaro and Sons. We are Trane Comfort Specialists certified in high-efficiency HVAC systems and indoor air quality. As we like to say, “Ongaro and Sons puts the V back into HVAC.”