Wood stove restrictions were imposed in Spokane on Tuesday after the National Weather Service expanded a stagnant air advisory to include most of Spokane County.
Spokane joined other areas east of the Cascades that are expected to see stagnant air this week. The Palouse region and North Idaho were not included.
The advisory is in effect until 4 p.m. Friday.
Under the restrictions, wood burning is limited to devices certified by the Environmental Protection Agency, which includes all burning devices sold since 1993.
The restrictions apply to Spokane’s smoke-control zone, which includes urban and suburban areas in the county.
Clean air agency officials are asking residents using certified appliances to burn as cleanly as possible by initially building a hot fire to get more efficient combustion and by using only dry, seasoned wood.
Fireplace burning without a certified insert is not allowed under the restrictions. In addition, outdoor burning is banned countywide.
Higher air pressure along the Pacific coast is causing cold air to be trapped near the ground, preventing it from mixing with milder air in the middle elevations. This normal fall and winter pattern leads to low clouds, fog and air pollution.
Air quality in Spokane on Tuesday was in the moderately polluted category. Forecasters were calling for a chance of snow flurries today. Highs are expected to reach the middle and upper 20s, with lows in the teens.
Late-night and early-morning fog are likely through the weekend. When the fog lifts, expect to see low clouds.
Forecasters said the conditions are likely to persist through at least next Tuesday.