Air quality: tips for smoke season and indoor air safety
Photo credit: Heather Drugge
Breathing is what we do day-in and day-out, and the quality of the air we breathe is an important contributor to our individual and collective health.
With wildfire season upon us – and smoke already affecting millions across North America – we can expect it to reach the North Shore before long. So, I’d like to share some of what I’ve learned over the past few years on a personal journey, learning more about air quality:
How it’s measured, and what measurements are most important
Best sources of information, especially for wildfire smoke
I’ll also cover some effective ways to clean the air inside our home, ensuring our family gets as many hours per day of clean air as possible, even when it’s smoky outside.
Outdoor air quality
During wildfire season, these are the resources I use for seeing smoke forecasts and live air quality information. The key metric to look for is called “PM2.5” (Particulate Matter 2.5 µm), fine particulate matter that is very hazardous to human health.
www.FireSmoke.ca
See predictions and maps of air quality due to wildfire smoke for the next few days
Get a sense of how long a smoke event will last, and/or see if you may want to revise any travel plans
Built and maintained by UBC, with some excellent North Shore folk who work on it.
PurpleAir
Provides live air quality readings from a massive network of citizen-installed sensors.
This “citizen science” project lets individuals place relatively affordable sensors at their homes or businesses. A win-win - they get useful very local data, and the rest of us can see the data is shared anonymously.
Wildfire smoke pollution is highly localized (like wispy clouds/plumes) so the many sensors of PurpleAir usually give the most localized information. Government air quality stations are the gold standard as they are more reliably calibrated and do a more thorough job, but are fewer in number and slower to update. (see next section)
Combining government data with PurpleAir readings gives the best of both worlds: accuracy, professional calibration, and real-time, localized detail.
Day-to-day I use this PurpleAir data through an an app called Paku, and I’m able to put live, very local air quality and temperatures as a widget on my phone, or even on my watch
BC Government Air Quality Stations
These stations provide the most comprehensive air quality measurements, tracking pollutants like:
PM2.5
Ground-level ozone (O₃)
Nitrogen dioxide (NO₂)
Sulphur dioxide (SO₂)
They also calculate an Air Quality Health Index (AQHI) score as a summary, making this complicated science simpler to use, and is a Canadian standard.
However, for wildfire smoke – which tends to be highly localized – the denser network of PurpleAir sensors are often more useful.
Mahon Park is the best, and only central North Vancouver sensor.
Indoor air quality
When AQHI values reach 4 or higher, we start to focus more on the quality of air inside our home – especially in the rooms where we work and sleep.
While commercial buildings may use high-grade filters and CO₂ monitoring, most homes (especially older, single-family homes) do not. Here’s what I’ve learned firsthand about managing indoor air quality:
Smoke can penetrate indoors quickly, even with windows closed.
HEPA filters are very effective – both for smoke and for seasonal allergies.
Cooking, especially burning food or frying, can create indoor PM2.5 spikes.
Closed bedroom doors at night led to surprisingly high CO₂ levels in our home.
(our home is not well-sealed, nor modern)
Our setup: HEPA filter and PM2.5 sensors
When our son was born, I bought a portable HEPA filter for his room to prepare for smoky weather. Later, I added a separate PM2.5 sensor, which came with additional features like CO₂ and radon monitoring that have proven very interesting. Radon gas is a leading cause of lung cancer in Canada, second only to smoking.
The portable HEPA filter worked well – it was quiet and also helped with my seasonal allergies. Once I started using the PM2.5 sensor alongside it, I could actually see the filter’s impact. Even on smoky days, the sensor would show elevated levels, and when I turned on the filter, PM2.5 readings dropped within minutes.
Since exposure over a 24-hour period is what matters most for health, knowing my son was breathing clean air for 12+ hours at night gave me peace of mind. Soon, I added filters to our other bedrooms too. The sensor also helped me decide what filter setting to use – high or low – depending on the PM2.5 levels.
The products below are not required - I've tried several over the past 7 years, so I’m sharing what products I’ve found useful and worked the best for me. At the end of the article I include some links to similar sensors you can borrow from local libraries.
Airthings ViewPlus
I tried several PM2.5 and CO2 measurement sensors. This one is by far the best, and includes built in Radon sensing, VOC (Volatile Organic Compounds), Temperature, Humidity, and air pressure. It's an excellent device!
PM2.5 from cooking
Once I started using the sensors daily, I noticed occasional unexplained spikes in PM2.5 — which I soon traced back to cooking. A smoky grilled cheese, pancakes, or overdone toast would all cause noticeable indoor air pollution. It’s the 24hr exposure that really matters, so spikes weren’t a reason to panic, but it has helped me recommit to using the stove ventilation fan more than I used to.
CO₂ accumulation in bedrooms
The sensor also measures CO₂ levels, a common way to gauge whether a room has adequate fresh air. Commercial systems usually increase air flowwhen CO₂ rises above 800 – 1000 parts per million (ppm). I found that with bedroom doors closed overnight, levels reached over 1500 ppm, high enough to start to cause headaches and reduce sleep quality.
This surprised me, especially since our home is older and not well-sealed. That insight prompted some changes to our routines – like keeping doors ajar or cracking a window – to keep CO₂ levels below 1000 ppm at night.
Final thoughts
Clean air, like clean water, is one of the foundations of healthy living. Since we’re breathing all the time (hopefully!), ensuring our family gets 8+ hours of good-quality air every night felt like a worthwhile focus.
I hope this has given you some good basic information and helps you improve the air quality in and around your home, too.
📚 Borrow an air quality sensor from a North Shore library
Good news — our local libraries offer air quality sensors you can borrow, so you can try some of these ideas out for yourself.
No north shore libraries I know of currently have PM2.5 sensors, but if we ask DNV, CNV, DWV (with a link to this article), I think they would add PM2.5 sensors to the library.
CO₂ Sensors
Radon Sensors
_____
Please sign up for our Better North Shore mailing list if this article resonates with you and your values. We're building a group of like-minded people who want to see the vision outlined on these pages and enjoy local articles like this one.
