For the first time in more than a decade, air-quality authorities issued a stage-2 burning ban Monday, meaning all indoor wood-burning and outdoor burning is prohibited except in homes where there’s no other source of heat.
The Spokane Regional Clean Air Agency posted the ban after air quality deteriorated quickly during the day.
The National Weather Service issued an air stagnation advisory Monday for nearly all of Eastern Washington and low-lying areas in northeast Oregon.
Margee Chambers, public information specialist for the clean air agency, said pollution levels soared during the day, forcing the agency to bypass a partial stage-1 ban that limits indoor wood-burning to certified stoves and fireplace inserts only.
“Today, the pollution levels spiked so quickly,” she said Monday.
One measuring site on Broadway Avenue registered 40 parts per million of fine particulates in the air. Action to ban burning can begin at 25 ppm. Wood smoke is the primary offender.
It is the first stage-2 burn ban in Spokane since April 1998. Another stage-2 ban was called in February 1993.
A stage-1 ban was last ordered in Nov. 2007 and lasted for five days, Chambers said.
Cold, heavy air left over from last week’s arctic front has been hugging the ground for several days allowing pollution – mainly wood smoke – to build up.
The air stagnation advisory means that pollution levels could rise to unhealthy levels until Thursday morning when a new Pacific storm will have a chance to clear the air. The advisory was in effect for areas below 3,000 feet in elevation.
In Spokane, the air quality index was at 87, in the moderate range, about noon and then went to 90 by 3 p.m. when the ban was ordered. Air quality is considered to be unhealthy for persons with respiratory problems at 100 and higher. Persons with breathing problems are advised to stay indoors and limit physical activity.
Higher air pressure has been creating downward motion in the atmosphere, preventing the trapped air at the lower elevations from mixing with cleaner air. A persistent layer of stratus clouds appeared over the region Monday, a sign that stagnant conditions were in place.
Air stagnation in the Puget Sound region led to a series of stage-1 and stage-2 burn bans in that region on Sunday. Air quality experts said some of that polluted air may be pushed eastward by a Pacific storm that is expected on Tuesday evening through Saturday. Gusty winds are expected on Saturday, and that should clean out the region’s air.