The B.C. Ministry of Environment has issued a wildfire smoke advisory for Prince George and six other Central Interior communities.
"Avoid strenuous outdoor activities," officials said in the advisory, issued shortly after 11 a.m. today.
"If you are experiencing any of the following symptoms, contact your health care provider: difficulty in breathing, chest pain or discomfort, and sudden onset of cough or irritation of airways.
"Exposure is particularly a concern for infants, the elderly and those who have underlying medical conditions such as diabetes, and lung or heart disease."
The advisory also covers Vanderhoof, Quesnel, Williams Lake, Burns Lake, Houston and Mackenzie and their surrounding areas due to forest fire smoke.
Smoke concentrations will vary widely as winds and fire behaviour change.
The city's Free Fare for Clean Air, offering free public transit kicks into effect at midnight and is lifted on midnight the day the advisory is lifted.