Cook County advises masks, clean-air rooms during hazardous air-quality event

As the Air Quality Index continues to reach hazardous levels, Cook County health officials are urging residents to stay indoors and avoid strenuous activity. Air quality worsened noticeably Tuesday as wildfire smoke intensified across the county, turning the sky orange and leaving ash on surfaces.

Smoke from wildfires burning across the Arrowhead region and along the Canadian border continues to affect the area, resulting in prolonged periods of poor air quality.

The AQI scale ranges from green, indicating good air quality, to maroon, indicating hazardous conditions. Thursday marks the third consecutive day Cook County has been rated in the maroon category.

“So that is the worst air quality that is possible on this scale,” Public Health and Human Services Director Grace Grinager told WTIP. “So when we hit that hazardous level, the air quality is extremely poor, and the advice is for everyone to be inside.”

If people must go outdoors, health officials recommend wearing a respirator mask. Public Health Supervisor Avi Sukhwal said Cook County Public Health and Human Services has masks available for the public. The county is also staffing the Cook County YMCA, where masks and water are being provided to people seeking relief from current conditions. North Shore Health is distributing N95 masks to those who need them.

“I would say wearing a mask is the best protection, but to avoid strenuous activity outdoors while the air quality is as bad as it is,” Sukhwal told WTIP.

Anyone experiencing headaches, shortness of breath or other symptoms related to poor air quality should call 911.

Grinager encouraged residents to create a “clean-air room” in their homes.

“That’s a room that you’re really taking the time and energy to make a place for you to feel comfortable physically and to not be exposed to the poor air quality outside,” Grinager said.

Ideally, the room should be a bedroom with an attached bathroom. Grinager advised against using kitchens, as cooking can further reduce indoor air quality. Clean-air rooms should also be free of candles, smoking, cleaning products and other sources of indoor air pollution.

For those without air purifiers, Grinager encouraged residents to build a do-it-yourself filtration system using a box fan and a furnace filter.

“That can also serve as a cooling mechanism,” Grinager said. “If you put an air filter on the backside of a box fan, open your window, and have it run for a while, it can bring air into your house.”

Grinager said families should spend as much time as possible in clean-air rooms, including while sleeping.

Both Sukhwal and Grinager encouraged residents to prepare not only for the current air-quality emergency but also for future smoke events, which they said are becoming more common as wildfire seasons lengthen.

“This is something that is related to changes in the climate,” Grinager told WTIP. “The season for wildfire events is longer. The volume of fires is larger, and I think from an air quality perspective, that means that all of us should expect these prolonged periods of poor air quality to become more frequent in the future.”

The National Weather Service’s Air Quality Alert remains in effect through Friday, July 17. Rain showers forecast later this week could help improve conditions across Cook County. Still, Grinager said residents should use the current event as an opportunity to prepare for future emergencies.

“I would just encourage people to take this seriously,” Grinager said. “Wear that mask. Limit your time outside. Set up your clean air room, and it’s going to be better overall.”

WTIP spoke with Grinager and Sukhwal about current air-quality conditions and ways residents can protect themselves during smoke events. Audio of that conversation is available below.

Josh Hinke July 16, 2026