IAQ is short for indoor air quality and it's a timely topic these days. The health effects, both short term and long, of poor indoor air are well-established. But how do you know if you home or office has a problem to begin with?
First, take a look around.
You can draw some conclusions about your indoor air quality by considering your lifestyle and home. See if any of these apply: You have a gas oven and cooktop and love to cook. Your heating system is long overdue for maintenance and could be leaky. Someone at home smokes. You've got a dog. Or a cat. Or both. You work or live near known sources of outdoor pollution—highways, factories or where the Air Quality Index (AQI) is sometimes (or often) above safe levels.
Wait, there's more. You burn candles, have a well-used fireplace or a wood stove. Or all three. You notice fine soot or dust when cleaning. Perhaps you live in an area prone to drought and wildfires. Or your house is old and may have asbestos or lead paint. You've seen or smelled mold. Let's not forget seasonal pollen that triggers sneezing and other allergic reactions. And then there's the newest worry: airborne COVID-19 virus (more on that later).
Yes, the list is long and there are plenty of things to worry about. Keep in mind, though, it's unlikely that you have all of these pollution sources or at least all of them at the same time.
So, focus first on the known or most likely problems.
Next, find out the levels of specific indoor air pollutants in your home.
You may have a good idea already what your air quality issues are. If not, an effective way to measure IAQ is with an independent (not connected to an air purifier) indoor air quality monitor. Using a monitor, you can learn which pollution issues you have (or don't have)–including PM 2.5 and PM 10 concentrations, as well as the presence of gases and VOCs.
An air quality monitor provides ongoing reassurance and precise, independent information on levels of specific pollutants. Many air purifiers include an integrated particle counter or other form of IAQ monitor, but these are often limited in capability, and they are usually housed on the air purifier–where the air quality will be much cleaner than in other parts of the room. Another issue: on-board monitors can lose calibration over time, making readings inaccurate.
When shopping for an IAQ monitor, choose one that's easy to use and that measures the specific types of pollutants you are most concerned about, such as PM 2.5. Not all monitors measure all pollutants, so check the specs before buying. For suggested products, take a look at the New York Times' Wirecutter site.
So, with what you know now, what do you do next?
Once you know your specific IAQ issues, follow this three-part strategy from the EPA:
• Controlling or removing the source of the problem
• Air purification using portable air cleaners or in-duct systemsSource Control
Your first line of defense is to remove the source(s) of pollution. Specific volatile organic chemical (VOC)-generating products—air fresheners, paint strippers, and other offending products offending products can simply (although not always easily) be removed from your home. Asbestos and lead can be professionally removed or capped; Mold and radon can be remediated. Gas stoves can be vented to outside; Chimneys and flues checked for leaks. Taking steps to remove any sources of indoor air pollution is your essential first step.
For in-depth guidance, review this EPA Checklist for Source Control.
It makes sense: increasing the amount of outside air can reduce the concentration of pollution indoors. Natural ventilation—opening windows and doors—is easy and effective, although care must be taken if the air quality outside is worse than indoors. One way to measure outside air quality is to look at the EPA’s published AQI or Air Quality index for your location. If your AQI is acceptable, and the weather cooperates, opening the windows is simple, fast, and effective. A home heating or cooling system that introduces outside air can also provide some ventilation, as it dilutes indoor pollutant concentrations with fresh air. If you have an in-wall or in-duct system, check to see if it introduces fresh air—not all do. Older homes achieve some ventilation, unintentionally, through leaky windows and doors. So that draft you might complain about isn't all bad. Unless the outdoor AQI is a problem. Ventilation is particularly important when you are creating significant pollution through use of VOC-generating-products (such as some cleaners, bleach, paints, paint strippers), smoking, or when cooking using a gas stove or oven, especially one that is not vented to the outside.
Air cleaners or air purifiers (the names are interchangeable) are the third element in the EPA guidance and, like ventilation, work well in combination with source control. Particle removal air cleaners can be in-duct, whole-house systems or portable.
What kind of air purifier?
HEPA and mechanical air cleaners or air purifiers are not designed to remove gaseous pollutants and VOCs released into the air. Some gasses and VOCs are removed using activated charcoal, often added as a supplemental filter to a particle air cleaner. However, the activated charcoal used with most air purifiers is of such a small quantity, and it is spent so quickly, that it isn’t an effective solution and provides a false sense of security. With a significant VOC problem, you may want to look at a VOC-specific removal technology along with source control.
If Your Focus is Particle Pollution
Particle pollution is typically the biggest issue in most homes. Particles include everything from ultrafine viruses and gas stove emissions to smoke, dust, pet dander, and pollen. PM2.5 (invisible particles smaller than 2.5 microns) is one of the top five environmental health problems indoors, according to the EPA.
Finding an air purifier up to the task will depend on two things: how good it is at capturing particle pollutants (efficiency), and at what rate it can collect them (effectiveness). This in turn depends on how much air can flow through the air purifier, measured by the Clean Air Delivery Rate. An air purifier that does a good job of capturing particles but has low airflow isn't the right choice, because it is efficient but not effective.
HEPA/HEPA-style air purifiers, using a mechanical filtration technology, push the air through a very dense filter, blocking and trapping particles. Unfortunately, this technology causes the filter to start clogging as soon as it is put into use, so the airflow diminishes. This clogging means HEPA filters need very, very frequent changes to stay at peak performance, making them costlier and less convenient than you may have expected. As well as less effective.
New Advanced Particle Removal Technology (APART™) keeps airflow high as particles are captured, because they are not forced through a filter at all. Instead, they are pulled out of the air flow into a disposable collection cartridge, for an efficient and effective solution that eliminates frequent filter changes. An alternative to HEPA and HEPA-style mechanical filtration, this patented technology is found in Brio air purifiers. Learn more about Advanced Particle Removal Technology and Brio
What about COVID-19? Can an air purifier help?
The simple answer is a qualified "yes" as long as you keep in mind that "help" means an air purifier can be part of a plan but isn't the plan by itself. According to the EPA, "When used properly, air purifiers can help reduce airborne contaminants including viruses in a home or confined space. However, by itself, a portable air cleaner is not enough to protect people from COVID-19. When used along with other best practices recommended by the Centers for Disease Control and Prevention, operating an air cleaner can be part of a plan to protect yourself and your family." For more information, read the EPA position on air purifiers and COVID-19.
Learn more about Particle Pollution, PM 2.5, and Health.