Thanks to the partnership with the Comox Valley Regional District and their successful grant application to the BC Lung Foundation as part of the Regional Airshed Protection Strategy 2023, the Town of Comox received three monitors to support the network and data within this region. PurpleAir monitors were installed on three public buildings - Town Hall, Comox Community Centre, Municipal Works Yard in the summer of 2024. The monitors measure fine particulate matter (also known as PM2.5), which hinders the air quality in the Comox Valley.
By increasing the number of air monitoring locations, we can learn more about how PM2.5 concentrations vary in our neighbourhoods over time. PurpleAir monitors are low cost air quality sensors that use laser particle detectors to measure PM2.5 concentrations in the air. Real-time readings from these sensors are available online at:
https://map.purpleair.com/
The BC Ministry of Environment and Climate Change Strategy endorses the use of PurpleAir monitors and has created data management tools to include measurements from these devices in the provincial air monitoring dataset.
Understanding the Readings
Readings from PurpleAir monitors indicate the amount of PM2.5 in the air at a specific location, at a moment in time. The higher the number, the more PM2.5 in the air. The monitors are responsive to local sources of PM2.5, so the measurements may change quickly.
- PurpleAir monitors are sensitive to humidity, so a correction factor must be applied to allow for an accurate comparison to the BC Air Quality Objectives.
- Corrected measurements are reported on a map hosted by the University of Northern British Columbia (UNBC) Atmospheric Sciences program: UNBC Hourly PM2.5 Observations map
- The BC Air Quality objectives for fine particulate matter are:
- 25 ug/m3 (micrograms per cubic meter), averaged over a 24-hour period; and
- 8 ug/m3 (micrograms per cubic meter), averaged over a year.