How to Protect Yourself From Wildfire Smoke

Wildfire smoke is a growing health threat, even for people living thousands of miles from the flames.

”Part of climate change is extreme weather patterns that include more winds that spread smoke more widely,” says Mary Margaret Johnson, MD, PhD, a research scientist with the Harvard T.H. Chan School of Public Health in Boston.

This smoke poses serious risks, especially to some vulnerable groups.

People exposed to wildfire smoke may experience minor issues like stinging eyes, scratchy throats, and headaches, as well as more severe reactions such as difficulty breathing and heart attacks.

”Wildfires cause particulate matter pollution, which is one of the largest environmental health risk factors contributing to premature deaths worldwide,” says Rebecca Saari, PhD, an associate professor of civil and environmental engineering at the University of Waterloo in Ontario.

• Headaches
• Irritated eyes and sinuses
• Runny nose
• Increased coughing and scratchy throat
• Fatigue
• Chest tightness

”If you feel extreme shortness of breath or chest pain that’s concerning, you will want to get to an emergency room or call 911,” says Timothy Daum, MD, a pulmonologist with University of Michigan Health–West in the city of Wyoming.

Those who already have underlying lung issues — such as chronic obstructive pulmonary disease (COPD), asthma, and bronchitis — face a higher risk of breathing difficulties. ”Smoke adds insult to already-injured lungs,” says Purvi Parikh, MD, an allergist and immunologist with NYU Langone Health in New York City and a medical adviser for the Allergy and Asthma Network.

As Dr. Daum stresses, pollutants caused by wildfire smoke can also aggravate chronic cardiovascular issues. People with heart disease should be on the alert for signs of heart attack, stroke, and arrhythmia (irregular heartbeat).

”When this small particulate matter gets into a person, it sets up inflammation and adverse consequences throughout the body,” says Daum.

”Damage to heart, vasculature, and lungs can be permanent, and it can be fatal,” says Otis Brawley, MD, a professor of oncology and epidemiology at Johns Hopkins University in Baltimore.

These minute pollutants, which are just 3 percent of the diameter of a human hair, are particularly hazardous. The body can filter out many coarser particles, but PM2.5 can penetrate deep into the lungs and impair their function.

Dr. Johnson cautions that it doesn’t take much of a rise in PM2.5 to ignite health problems. ”With just a 10-unit increase in PM2.5, you’ll see an uptick in emergency room visits and hospital admissions for heart attacks, strokes, arrhythmias, and severe breathing problems related to asthma, COPD, or bronchitis,” she says.

”When the level reaches 200, it’s like smoking almost 9 or 10 cigarettes a day, and that’s for everyone — babies and older people included,” she adds.

When air quality veers into the danger zone, take these steps to protect yourself:

Avoid going outside. One of the easiest actions to minimize smoky air intake is to stay indoors. The CDC instructs people to keep windows and doors shut, and run an air-conditioner, but keep the fresh-air intake closed and the filter clean to prevent outdoor smoke from getting inside. Those without air-conditioning may want to seek out an air-conditioned community center.

If you do want to go outside during a period when wildfire smoke is high, Johnson suggests that conditions may be somewhat better at night or early in the morning or later in the day when there is less sunlight.

Daum adds, however, that there is no reliable time of day that is better than any other when it comes to air quality.

Those calculations are translated into an air quality index (AQI), a number ranging between 0 and 500. A level between 0 and 50 poses no health dangers. Members of vulnerable groups may start to have air pollution–related symptoms starting at 51, and at 100 the air outside is considered unsafe for them. Most people will start to have noticeable symptoms at a level above 150, and anything above 300 is considered hazardous.

Keep exercise indoors and to a minimum. Physical activity increases breathing and heart rates, so when air quality levels go into the red, exercise inside and at a moderate (rather than high-intensity) pace. ”Overexertion should be avoided,” says Dr. Brawley.

Wear an N95 mask. Daum advises wearing an N95 mask that fits snugly to the face if you’re outdoors for a long time. ”A regular cloth mask or regular surgical mask probably won’t do much. An N95 probably won’t filter out everything, but it will help.”

• Wildfires can worsen air quality and increase the risk of both minor ailments and serious events like heart attacks.
• This is due to microscopic particulate matter in the smoke, which can get into the lungs and lead to damaging inflammation.
• Checking the Air Quality Index (AQI) on weather apps or from the EPA can give you an idea of whether it's safe to go outside during wildfire season.