Air quality predicted to stay in moderate-to-unhealthy range Wednesday

Northeast winds dispersed much of the smoke that hung over Spokane on Sunday and Monday, but the Spokane Regional Clean Air Agency predicts a directional change could bring more smoke to the region.

Air quality swung between moderate and unhealthy Tuesday and is predicted to do the same Wednesday with the worst air expected in the evening hours, according to Spokane Regional Clean Air Agency predictions. The agency advises avoiding heavy exertion and carefully planning outdoor time and urges those who may have asthma, heart disease or be sensitive to smoke to watch for symptoms such as coughing and shortness of breath.

The agency also warns that dust masks commonly available in hardware stores can only protect from large particles, like sawdust, and will not shield lungs from the fine particles in smoke. Respiratory masks marked N95 or N100 can filter out some fine particles, but not carbon monoxide, formaldehyde or acrolein. They are available at hardware and home repair stores as well as pharmacies.

Wheat field fire claims 66 acres

A North Idaho wheat field caught fire late Tuesday afternoon, burning 66 acres and briefly closing state Highway 41.

Mary Fritz, spokeswoman for the Department of Lands, said the fire is under investigation and authorities believe it is human-caused but not arson. The fire was contained Tuesday evening by the Northern Lake Fire Protection District, Kootenai County Fire and Rescue and the Idaho Department of Lands.

Six engines, three water tenders and 30 firefighters fought the fire, containing it in only a few hours. Fritz said fires that spark in wheat fields are often extremely smoky but are usually easier to corral than timber fires. Once a field burns, she said, there isn’t much residual fuel left.

Fritz said the fire started near Highway 41 and West Hayden Avenue between Post Falls and Hayden, The blaze didn’t threaten structures, she said.