She often keeps Liam indoors and uses air filters to purify the air inside. These neighborhoods often have fewer trees and are hotter — and people who work outdoors don’t have the luxury of air conditioning and indoor air purifiers. Protect your family’s health during heavy wildfire smoke by staying indoors and keep the air as clean as possible using air conditioning if you have it (on recirculate mode) or a high-efficiency particulate air (HEPA) purifier.