Pollution has prompted an air quality advisory for Houston.
The environment ministry and Northern Health say high concentrations of fine particulate matter are to blame.
People with chronic medical conditions should postpone strenuous exercise until the advisory is lifted.
Those with heart or lung disease, diabetes as well as the elderly and infants are the most vulnerable to fine particulate exposure.
Woodstove use is banned within the District of Houston during the advisory unless it’s the only source of heat.
