Editor’s note: This is a developing story that’s been updated since it was first published. Healthline will continue to update this article when there’s new information.

Wildfires have erupted across California in recent weeks burning tens of thousands of acres in both the northern and southern parts of the state. The intense fires have stymied fire fighting efforts as they’ve burned through homes and businesses.

And the danger isn’t limited to the immediate surroundings. The fires are also producing enormous smoke plumes which are drifting miles beyond the flames.

As a result, many people — even those dozens of miles away from flames — are at risk for asthma attacks, respiratory distress, and cardiac events due to the increased air pollution.

Across California, the smoke and haze has led some residents to wear masks to protect themselves from the smoke.

But do these masks do much to help?

How to protect yourself

Dr. Robert Blount, assistant professor of pulmonary pediatric and adult medicine at the University of California San Francisco, told Healthline in an earlier interview that if people can smell or see smoke, they should take steps to protect themselves.

“If there’s enough smoke that you can see it or smell it… then it’s a dangerous level,” he told Healthline.

For extra protection, special face masks called respirators can help.

These masks can provide protection from the small microscopic particles in smoke that can damage the lungs.

Children, the elderly, and people with lung or cardiac conditions are at the highest risk of developing symptoms, Blount explained.

“People need to be pretty careful about heavy smoke exposure,” he said.

Dr. Naveena Bobba, the director of public health emergency preparedness and response at the Department of Public Health in San Francisco, said in an earlier interview that if people start to have symptoms related to the smoke they should stay inside and seek out buildings with filtered air.

“They should also go indoors to a place that has a good HVAC system,” Bobba told Healthline.

If smoke or haze makes its way indoors, Bobba advises running an air conditioner to try and keep out the worst of the pollution. She also said air filters can help clean out the air if a person doesn’t have an air conditioner.

As a last resort, Bobba said people can head to a newer building like a mall or movie theater to stay out of the polluted air.

“Good hydration is also very important so drinking lots of water [can help],” she added.

A mask can protect against smoke, but it doesn’t work for everyone

The California Department of Public Health advises only certain masks will work and other common types of face masks, like surgical masks, won’t filter out the harmful particles.

Without the masks or other protection, microscopic particles from smoke can travel through the lungs to exacerbate respiratory diseases like asthma.

It can even raise the risk of cardiac events such as heart attack or stroke.

“Wildfire smoke has a higher proportion of particulate matter in the air — so solid matter — that can be filtered out,” Blount said. As a result, these masks, “can be very effective” at keeping out pollution.

The only types of masks that should be used are labeled with N95 or P100. These “respirators” or masks should be certified by the National Institute for Occupational Safety and Health (NIOSH).

The California Department of Public Health explained that the filter material rated 95 will capture “at least 95 percent of very small particles.”

The filter material rated 100 filters out “at least 99.97 percent.”

But these masks aren’t perfect and there are many people who many not benefit from wearing one.

The California Air Resources Board explained that people with facial hair cannot get an appropriate “seal” around the face to ensure there isn’t dangerous particles being inhaled. Additionally, children may be too small to use the mask safely and should mainly be kept away from smoky conditions.

Blount added that due to children’s small size, “they get a higher dose of the air pollution than adults.”