Wade reported from Tokyo and Tang from Washington.

“You can find these low-cost, indoor air quality monitors just about everywhere online now. They don’t cost all that much anymore,” he said.For most people, going outside for just a short time won’t have a negative long-term impact, said Sethi.

Wearing an N95 mask, which became common during the coronavirus pandemic, will help filter out the pollution.“N95 is going to get rid of 90-95% of the particles,” said Jennifer Stowell, a research scientist at Boston University’s Center for Climate and Health. “If you have access to a mask that has a respirator-type attachment to it, then that’s the very best.”If you must be outside and you experience symptoms, experts say you should head indoors or somewhere else with better air quality. Even if you are healthy, it’s good to take precautions.

“If you start wheezing, which is like this whistling sound of the chest, or if you’re feeling short of breath, that’s definitely more concerning,” Sethi said.Smoke from Canadian wildfires is visible at sunset in Oconomowoc, Wis., June 1, 2025. (John Hart/Wisconsin State Journal via AP)

Smoke from Canadian wildfires is visible at sunset in Oconomowoc, Wis., June 1, 2025. (John Hart/Wisconsin State Journal via AP)

Close the windows and turn on the air conditioner, if you have one, setting it to circulate the indoor air. Use blankets to cover cracks that allow outside air into your home, such as under doors.“I’m one of those players that doesn’t care,” said Gauff, a 21-year-old from Florida who is the No. 2 seed in Paris. “I can get up early. I’m not slow to wake up. Once I get some food in me, I’m pretty much good.”

Tennis is an all-day sport, especially at its, where ticket sales and TV contracts bring in millions and drive decision-making by organizers. The French Open, U.S. Open and Australian Open all have night sessions

; Wimbledon has an 11 p.m. curfew.So in Paris, for example, a match can start at 11 a.m. or 8:15 p.m. or anywhere in between — or, occasionally, much later. It is a frustrating aspect of the sport for the athletes or for fans hoping to see a certain player.