The free "OregonAir" app uses smiling and frowning emojis to show what air quality conditions look like in different parts of the state.
Those at particular risk include those with heart and lung conditions, as well as diabetics, infants, or the elderly. According to air pollution monitors, fine particle pollution is at or above a level that is considered unhealthy for sensitive groups.
Puget Sound-area residents should avoid vacuuming for up to a week as they wait for the wildfire smoke that has again descended over the lowlands to clear.
Smoke from B.C. wildfires can be seen more than one million kilometres away from Earth, and the province's communities are dealing with some of the worst air quality on the planet.
"Wholesale improvement to air quality is not likely until midweek".
They also have just 19 out of possible flawless 100 on a worldwide air pollution index called the Breezometer.
Environment Canada warned that some of the particulate matter is small enough to "easily penetrate indoors" and said infants and seniors were among the people most likely to feel respiratory symptoms.
Officials say air quality over the area is poor because of smoke from wildfires and terrain that traps smoke in valleys. All you need is a MERV 13 furnace filter and a bit of tape. A typical surgical mask won't do the trick.
Planes at Seattle-Tacoma International Airport were grounded for a few hours Sunday due to low visibility, according to the Federal Aviation Administration.