Much of the Pacific Northwest has been covered in a blanket of smoke for over a month.

For the state of Montana, an air quality alert has been issued for nearly all residents. When smoke from wildfires is in the air, state and local health officials recommend that people with respiratory or heart disease,the elderly, and children should avoid any outdoor activity.

Now, doctors from the Washington State Department of Health are warning that vacuuming can kick up particulate matter, potentially making unhealthy air even worse.

"Don’t vacuum unless your vacuum has a HEPA filter, because vacuuming stirs up particles already inside your home. Don’t smoke, because smoking puts even more pollution into the air."

Montana residents should avoid vacuuming for up to a week as they wait for the wildfire smoke that has again descended over the lowlands to clear.

In addition, health officials advise that the most effective air cleaners have a HEPA filter. HEPA filters can reduce the smoke particulates in indoor air. HEPA filters with charcoal can also remove or reduce the amount of some other harmful gases from indoor air. These air cleaners should be used in the room where you spend most of your time, which is often a bedroom.

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