Air filters in high demand as smoky skies move into the Bay Area after extended heat wave

SAN FRANCISCO (KGO) -- The smoky haze spreading across the Bay Area Friday is bringing back memories of the heavy, orange smoke that shrouded the area two years ago to the day because of massive wildfires.

Smoke -- from the wildfires burning in El Dorado County and in Oregon -- is making its way to the Bay Area.

Right now, there's no Spare the Air alert, but experts say they're closely monitoring air quality throughout the region for smoke impacts from wildfires.

2 YEARS AGO: Dramatic photos capture orange, hazy skies seen all across San Francisco Bay Area

"A lot of that smoke is aloft, so it's not at the ground level," said Walter Wallace of the Bay Area Air Quality Management District. "That's why calling it an advisory and not a Spare the Air Alert. So, for the most part, we're expecting air quality to be in the moderate range and not to have any kind of exceedances."

The smoke in the sky can make some people really sick.

"The fine particulate from PM 2.5 that's in wildfire smoke can cause exacerbations of disease in people with preexisting heart and lung disease and asthma is a prime example," said Dr. John Balmes, a UCSF Professor of Medicine.

RELATED: Evacuation orders in effect for Mosquito Fire in Placer, El Dorado counties

Doctors say the best way to protect yourself is to stay inside and use a HEPA filter or air purifier.

"Since the big fire happened a few years, in Napa Valley and Sonoma we have an air purifier for each room of our house. It's amazing that we have it on 24/7 for the past few years," local resident Francesco Covucci said.

At Cole Hardware in North Beach, air filters are in high demand.

"If the air quality goes down, we start selling them," supervisor Dan Mendoza said.

RELATED: Will new regulations do enough to keep homeowners from losing fire insurance?

But experts say you need to use them properly.

"Windows have to be closed so it doesn't pull in bad air from outside because that will overwhelm the filter," Dr. Balmes said. "You have to properly size the device to the room. It's called the clean air delivery rate and you have to make sure it's appropriate for the size of the room you are trying to clean

As hot weather and wildfires become more common across California, Bay Area residents are learning to deal with the long-lasting effects.

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