The Bay Area Air Quality Management District has extended an air quality advisory through Saturday because of smoke persisting in the region from wildfires further north in California.
The smoke has caused worse air quality than last week, when the air district also issued advisories, but it is not expected to exceed federal standards or prompt a Spare the Air alert.
The public can track air quality readings in various Bay Area locations on the Bay Area Air Quality Management District website. You can also check the air quality in your neighborhood by using an interactive map here.
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"The advisory is in place because we just know that there’s smoke out there," Aaron Richardson with BAAQMD said. "People are going to see it and there may be localized impacts and potential spikes at periods during the day."
If people smell smoke, they are encouraged to stay inside with their windows and doors closed until the smoke clears, the air district said. People are also urged to set their air conditioning systems and car ventilation systems to re-circulate mode to keep the smoke out.
Kaiser Permanente pulmonologist Dr. Thomas M. Dailey said the current situation sets up a unique challenge: it’s tough to be outdoors with the smoke and indoors with the risk of COVID-19.
"We’re getting caught between a rock and a hard place," he said.
He said people should wear a well-fitted N95 mask if they have to go out because a simple cloth mask won't protect them.
He also pointed to new research from Harvard showing wildfire smoke, which causes lung inflammation, making people's lungs more vulnerable to COVID-19.
"This makes sense, that these particles wedge into the lungs, cause inflammation and make you more susceptible to illness," he said. "And if you do become ill, more likely to have a more severe case."
Walnut Creek had some of the worst smoke Wednesday. N95 masks and air filters were a hot item at the downtown Ace Hardware.
"The next few days, we’ll start to see this [filter aisle] become empty," Chuck Judd said. "We’ve been preparing for this moment all year long. So, I expect to see it empty but refilled."
Bay City News contributed to this report.