How to Protect Your Household’s Health
by Ron Hartling
While you can do little if anything to change the particulate concentration of outdoor air at any point in time, there are measures which you and your loved ones can take to limit how much of those pollutants you actually inhale. Those measures all require that you inform yourself of the current outdoor readings, which you can do by simply referring to this site each morning or, if you prefer, by clicking on the link “Current and Recent Ontario Particulate Concentrations” under the Links menu item above. Whichever you choose, make it a prominent “Favorite” so that you can get to it with one click. This site includes a next-day forecast which, coupled with the current reading, can facilitate an informed decision as to whether or not you should leave windows open overnight during the summer months.
Realistically, protecting yourself implies reducing your cumulative annual exposure to something lower than the WHO limit; i.e., significantly lower than typical Kingston outdoor air quality. It’s up to you to choose your preferred level by balancing the health risk reduction against the time, money and effort you are prepared to invest in achieving your objective. Because you have limited control over your particulate inhalation when you are away from home, your at-home air quality goal should ideally be kept sufficiently low to balance out the time away.
For outdoor exposure, you only have two choices: to limit the time you spend outdoors when Kingston PPM2.5 readings exceed your personal comfort level or to wear a quality, NIOSH-approved (for snug fit) N95 mask. Those may be hard to find in Canadian stores, but you can order them from Amazon. For myself this past summer, I decided on masking whenever Kingston readings exceeded 8 µg/m3, and staying indoors to the extend possible when they were above 15 µg/m3. I found that to be mostly doable.
For indoor air quality, HEPA-level air filtration is absolutely essential. I would strongly recommend that you buy a quality portable HEPA filter which incorporates a PM2.5 gauge so that you can accurately measure when that filter needs to be on, at what speed and for how long. While there are many choices, this particular model has worked well for me. It gets a large space down to a healthy 1 to 3 µg/m3 reading within 30 minutes to an hour depending on how bad the ambient air might be. I confirmed the accuracy of the gauge by running the filter briefly outdoors and comparing what it displayed to the most recent Kingston hourly reading. If you have a forced-air furnace and/or central home air conditioning, you should be able to reduce the load on your portable filter by installing a premium furnace filter with a MERV rating of at least 13 (see this explanatory article). Because the increased filtration will to some extent restrict air flow, it would be wise to ask the firm that installed your furnace whether a MERV 13 filter is appropriate. In my case, I was advised that my furnace could handle it provided that I changed the filter every two months. At an Amazon price of roughly $14 per filter in a six-pack, I deemed that eminently affordable given the value of better air quality throughout my home. If your air conditioning system automatically brings in outside air, you may have to figure out how to disable that during periods when outdoor air quality is poor. Since regular furnace filters are not true HEPA, the affordable alternative is multiple portable HEPA filters.
A do-it-yourself alternative: If you consider commercial portable HEPA filters to be overly expensive or prefer to be a do-it yourselfer, your alternative is to assemble a Corsi-Rosenthal Box (CR Box) from four MERV 13 filters and a box fan. Many have found those constructions to be at least as effective as commercial products. Click here for full assembly instructions.
During heat waves in July and August of 2023, I faced the dilemma of my house getting stifling when closed up during bad-air spells. Living as I do near Lake Ontario, I’ve never previously needed nor wanted air conditioning. Because of the requirement for external exhaust, standard room air conditioners would have been very expensive to install given that all my windows are casement. My planned long-term solution for this summer was to add a heat pump. While expensive, substantial government support is available (see the Sustainability Kingston website). Since summer heat waves can only worsen going forward and one becomes more vulnerable to extreme heat with age, it will be a worthwhile investment. Unfortunately, while I briefly got on the list for the appropriate government program, it was suspended in March when they exhausted their budget. I intend to try again as soon as the replacement program is announced.
For pregnant women: this peer-reviewed study compares the children of randomly-selected pregnant women who were given portable HEPA filters for indoor use to an equal-sized control group without, testing those children’s cognitive functioning when they reached four years of age. The former did significantly better in a wide range of cognitive functions, including 2.5 to 3.2 IQ points. As a grandparent, I can’t think of a better pregnancy gift than a nice HEPA filter!