Does my COVID mask protect me from wildfire smoke? Experts answer key questions

In recent days, Sacramento weather conditions have improved, reducing smoke in the air, but hundreds of wildfires continue to burn across California. This fire season brought novel challenges, since poor air quality limited the potential for outdoor activities — which officials had encouraged as a safer alternative during the pandemic.

It’s a complicated time, so The Bee spoke to several experts to get their advice on taking care of our health this fire season.

Check the Air Quality Index (AQI) before going outside

Kent Pinkerton, a UC Davis professor who researches air pollution and respiratory health, recommended California residents regularly check the AQI online or in the media. The AQI measures the concentration of five major pollutants in the air: ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide and particle pollution. Higher numbers mean more respiratory risk.

“An AQI of 51 to 100 can be problematic for people who may be somewhat sensitive,” Pinkerton said. “When it goes above 100 to 150, that’s an area where, especially if you’re highly susceptible, it could be very hazardous for you to be outdoors. Above 150 is unhealthy for absolutely everyone.”

The AQI in Sacramento reached 174 on August 22 but has since fallen closer to 100 (though it continues to fluctuate).

Know if you’re in an at-risk group

Air pollution affects people with pre-existing respiratory or heart conditions before it starts to bother everyone else, Pinkerton said. “For many people who are susceptible, they’ll find that even small amounts of smoke particles may significantly affect them.”

Older populations may also find that smoke bothers them more, said Irva Hertz-Picciotto, an environmental epidemiologist at UC Davis. Hertz-Picciotto said that to a lesser extent, small children may be more susceptible to pollution-related breathing problems, too.

UC Davis associate professor Rebecca Schmidt, who researches the effect of wildfire smoke on pregnant women and their babies, said numerous studies have shown that in vitro exposure to air pollution in general is linked to asthma and neurodevelopmental issues.

Although Schmidt’s study is still in progress and there is still little research on wildfires and pregnancy, pregnant women may want to be extra careful, staying inside as much as possible on days with poor air quality.

Choose your mask wisely

Unfortunately, COVID-19 and wildfires don’t require the same kind of mask. Public health officials have said standard cloth masks are primarily meant to prevent people from breathing coronavirus particles out into the air, whereas with wildfires, the goal is to avoid breathing pollution in.

N95 masks work best for smoke, experts said.

“N95 masks don’t allow the fine particles in,” Hertz-Picciotto said. “The smallest particles actually do the most damage.”

She added, however, that the filter on N95 masks could allow the wearer to exhale coronavirus particles through the valve. She advised placing a piece of tape over the filter and said air would still be able to enter through the rest of the mask.

If you can’t get an N95, keep wearing your COVID mask, Pinkerton said. It won’t do you any harm and it could still prevent you from spreading or catching the virus.

Exercise safely

Avoid outdoor exercise when air quality is low, experts agreed. The health risks outweigh the benefits. For reference, the Yolo-Solano Air Quality Management District has charted its recommendations for physical activity in various conditions.

Indoor workouts of any variety should be fine, provided the building has proper air filters. Although many gyms are closed, home workouts are a popular alternative. Pinkerton also suggested a stroll through the shopping mall rather than a walk in the neighborhood on particularly smoky days.

To make sure that your home air quality remains acceptable, check your home’s air filter, Pinkerton said. HEPA-approved filters work best. Note that filters may need to be replaced more frequently when air quality is poor.

This story was originally published August 28, 2020 at 4:00 AM.