Air quality from the Grays Creek Fire has suffered since the fire began last thursday, according to an air-quality monitoring station in McCall operated by the Idaho Department of Environmental Quality.
Air quality due to particulates was at its worst between 2 p.m. and 8 p.m. Sunday, according to readings taken at the station, located at the Krassel Ranger District office on Mission Street.
During that period. the one-hour Air Quality Index peaked at 361 at 3 p.m., according to the readings. The DEQ considers any reading over 300 to be "hazardous," meaning the entire population is likely to be affected.
A similar spike in poor air quality happened between 4 p.m. and 5 p.m. Monday, when the one-hour air quality index peaked at 350.
However, the DEQ measures air quality over 24-hour periods as far as health effects, and the 24hour air quality index in McCall ranged from about 50 to about 80 between the start of the fire last Thursday and Monday. Any reading between 51 and 100 is considered to be "moderate" air quality by he DEQ.
The 24-hour index began to rise toward mid-week, however, with the mark breaking 100 Tuesday afternoon, which was when the latest readings were available. An index over 100 is considered unhealthy for children, the elderly and those with health conditions affected by air quality, according to the DEQ.