Caring for the Air – Forest Fires, Air Quality Advisories, and Why Fraser Valley Smog is Worse in the Summer

Smog Formation in the Lower Fraser Valley from Metro Vancouver on Vimeo.

Forest fires outside our region are having an impact on air quality in the Lower Fraser Valley this summer. Elevated concentrations of fine particulate matter from those fires resulted in an air quality advisory being issued on August 23 for the central and eastern Fraser Valley, due to smoke from wildfires in Washington. During this type of advisory it is recommended that people with chronic underlying medical conditions avoid strenuous activities.  Advisories also offer tips for individuals to reduce their own health risks and help improve the quality of our air. But even without forest fires, air quality in the Lower Mainland can deteriorate in the summer. Here’s why sunlight and heat can equal smog in our region, especially in the Lower Fraser Valley.

Metro Vancouver is part of the Lower Fraser Valley, an area of land located between the Coast Mountains to the north and the Cascades to the south. Ground-level ozone can form in this valley when nitrogen oxides react with volatile organic compounds, or VOCs. Since sunlight and heat are important ingredients in this reaction, smog can become an issue during the summer on hot, sunny days with stagnant weather.

Sources of Smog

In the presence of sunlight, nitrogen oxides (NOx) and volatile organic compounds (VOCs) react together and produce ground-level ozone, one of the main components of smog. The primary sources of NOx are cars, trucks, buses, ships and other non-road equipment, and heating of buildings, while the main human-caused sources of VOCs are personal care and cleaning products, solvents, paints, non-road equipment, cars, trucks and vehicle refuelling at service stations.

Warm air and restricted flow are important factors in the creation of smog in the Fraser Valley

Due to warmer temperatures and restricted air circulation, summertime ground-level ozone tends to be higher in the eastern portions of Metro Vancouver, such as Maple Ridge, Pitt Meadows and Langley, as well as the Fraser Valley Regional District.

Reducing VOC  Emissions

Scientists have confirmed that VOC are the critical limiting factor to suppress ground-level ozone formation in Metro Vancouver, so Metro Vancouver is working to develop policy and program options to reduce VOC emissions. In the meantime, these are some steps you can take to go VOC-free or low-VOC in your daily life:VOC products

  • Switch to a low-VOC option: Where possible, look for the low-VOC option for household products. Paints are an example of a product where low-VOC latex-based options are readily available substitutes. For other products, such as nail polish remover, low-VOC options are available, but will require some sleuthing to find.
  • Avoid the aerosol: The propellant used in aerosol cooking sprays, hairsprays, deodorants, and other household products are VOC – typically propane, n-butane, and isobutene. This means that in addition to the VOC in the product itself, additional VOC are required to create the spray mist. Opt for hand pump or compressed-air based sprays; or switch to direct application versions, such as roll-on perfumes and deodorants.
  • Store smart: When storing products that contain VOC, do so in tightly-sealed, original containers. For gasoline, replace your old gas cans with cans that comply with emission and spill control standards. Or better yet, buy small amounts as you need it, so you don’t have to store these products!
  • Recycle: Properly dispose of products containing VOC. Many of these products are considered household hazardous wastes and should be disposed of at special facilities. For more information, see http://www. to find out where to dispose of various products.
  • Say goodbye to gas: Your gasoline vehicle is likely your most significant source of VOC in your home. Do away with gasoline altogether, by switching to electricity for your lawn and garden equipment and your vehicle.  Or go manual and get exercise too!
Learn more about Ozone and Smog

You can learn more about the interrelationships between VOC, nitrogen oxide, smog, and ground level ozone by downloading the 2015 Caring for the Air report (FOCUS on VOC – page 12).

Track The Current Air Quality in Your Neighbourhood

This web-app displays air quality and weather data from the Lower Fraser Valley Air Quality Monitoring Network in southwestern British Columbia, Canada. Metro Vancouver operates this network in cooperation with the Fraser Valley Regional District, Environment Canada and other partners.

Click on the picture to launch AirMap

Click on the picture to launch AirMap

Air quality advisory information and real-time air quality readings for Metro Vancouver and the Fraser Valley communities, along with potential health impacts can be found at:

Watch even more Metro Vancouver videos and our popular events such as the Sustainability Breakfasts and Zero Waste Conference. Check out our new and improved Video Gallery with a searchable index of hundreds of videos.

3 thoughts on “Caring for the Air – Forest Fires, Air Quality Advisories, and Why Fraser Valley Smog is Worse in the Summer

Leave a Reply