Photo: City of Prince George

Air quality advisories have been issued for Prince George and Vanderhoof as a ridge of high pressure keeps air from moving out while more pollutants are being added.

The Environment Ministry and the Northern Health authority say in a joint release that the advisories will remain in effect until further notice.

They say fine particulate matter from industry and residential wood burning is contributing to poor air quality, which may not improve until Friday as the high-pressure weather pattern breaks down.

The advisories say the concentration of particulate matter averaged over 24 hours has exceeded the provincial air quality objective in both areas, especially Vanderhoof.

People with chronic medical conditions are advised to postpone strenuous exercise until the air quality improves.

Residents are also being asked to avoid using wood stoves and fireplaces unless they are a sole source of heat.