It was illegal — just temporarily — to use fireplaces and stoves that burn wood or pellets in Multnomah County.
The restrictions, a step the county public health department rarely uses, took effect at noon Wednesday and lasted 24 hours, unless they are extended.
Air quality in Portland was rated as yellow or “moderate” Wednesday afternoon. County public health staff says it’s a good idea to turn on household air filters if you live with people who have asthma or other respiratory issues.
The poor air quality is expected to last at least through Thursday.
The public health department issued the burn ban in an effort to get ahead of pollution, amid rising levels of air pollution and a weather forecast of little to no wind and a temperature inversion. Those conditions can trap pollution close to the ground.
An ordinance the county passed a few years ago allows public health to act before the air quality becomes unhealthy.
Officials at Multnomah County Environmental Health began conducting daily forecasting in cooperation with the Department of Environmental Quality and the National Weather Service to identify potential poor air quality days. The seasonal wood-burning ordinance is in effect each year from Oct. 1 through March 1.
The burning restrictions do not apply to grills or cooking food.
People who rely on a wood stove as their primary heat source or who earn less than 60% of the Oregon median income can apply for an exception to the burn restriction rules.