“If you have a smoker in the home the particulate matter could be much higher indoors than outdoors,” she said. If you smoke and you can’t quit, do everything you can to avoid exposing other people to your smoke, like stepping outside. The same goes for people who vape.

Frying foods or cooking without good ventilation can also increase indoor air pollution. Nitrogen oxides from gas stoves are a known respiratory irritant, as is the fine particulate matter that is most likely wafting off your roasts. You should turn on the ventilation hood above your stove and open windows if you can.

One caveat: For people living in proximity to major sources of pollution, opening a window might not be a good idea. That’s where an air purifier might be worth the investment if you can afford it.

It’s important to think about allergens, too. If you smell anything musty around you home, you should investigate. “Mold aggravates asthma,” Dr. McCormack said. “This might be the time to address a damp spot or water damage problems.”

This might also be the time to pest-proof your home. Mice and cockroaches can provoke asthma. Dr. McCormack suggested filling cracks around the house that might let in pests and taking care to properly store food that might entice them.

Finally, if you’re taking maintenance medication for asthma, like an inhaler, don’t forget to use it. “Remembering to take it can be challenging, particularly at a time like this when we aren’t in the same routines,” Dr. McCormack said. But it’s an important step to protect yourself, particularly now.

“With indoor pollution, we have a lot of control over more aspects of our exposure,” Dr. McCormack said. “In addition to a source of risk, it’s a source of opportunity. It’s a good time to change habits.”