Air quality has worsened rapidly across the Wasatch Front in recent days, leading state regulators to warn Utahns against prolonged exertion outdoors.
With huge wildfires burning across Washington, Oregon, Idaho, Montana and Canada, the northern Utah counties of Box Elder and Cache already have more small-particulate pollution in their air than is considered healthy for the general population, according to the state’s air-quality monitors.
Salt Lake, Davis, Weber, Utah and Tooele counties have also exceeded the Environmental Protection Agency’s standard for small particulates, though their air remains less smokey in general than farther north.
“As residents of the Beehive state and others across the U.S. are learning,” wrote Jon Meyer, a climatologist at the Utah Climate Center, “you don’t need to have flames in your backyard to feel the negative effects a bad wildfire season can have on our daily lives.”
Bo Call, who oversees air monitoring for the state Division of Air Quality, said Wednesday he expects conditions will continue to worsen through Friday, unless some of the fires raging to the north subside or a storm front arrives to blow the smoke elsewhere.
“The nature of particulate [pollution] is it really doesn’t go anywhere until a front comes through and blows it out,” Call said, “unlike ozone that goes up and down every day.”
Ozone levels over the Wasatch Front continue to rise and decline with daily temperatures, sometimes spiking to unhealthy levels — a trend unrelated to smoke that has continued to fluctuate all summer long.
States across the West, meanwhile, are experiencing a severe fire season. This year’s weather — a wet winter that fueled early plant growth followed by a dry summer that turned it all to tinder — has led to several large and smokey blazes, some of them record-breaking in size.
Even though air and fire-fighting experts saw the problems coming, Meyer wrote in an email, “watching it all unfold has been troubling.”
A final tally on the 2017 fire season is still pending, he wrote, “but it is certainly pushing the envelope for what many states expect or plan to occur under a ‘bad’ year.”
The Utah Department of Health guidelines last year lowered the threshold for when students should be kept indoors due to poor air quality. They recommend all students remain inside when levels of fine particulate matter, known as PM 2.5, reach 55.5 micrograms per cubic meter — enough to earn either a “red” or “purple” on the state’s air quality color scale.
Officials in Ogden School District sent out information on the bad air Wednesday to school administrators, advising them of the poor conditions and suggesting ways to limit student exposure.
Call urged residents to use common sense about activity outdoors.
People with respiratory conditions such as asthma should stay indoors as much as possible and healthy individuals should pay attention to their bodies when outside. If they can smell or taste smoke or feel it burning their eyes, he said, they are advised to remain indoors.