Check on the vulnerable
CDC's at-risk groups — children, older adults, pregnant people, anyone with asthma, COPD, or heart disease — should limit time in a smoke-affected building until it's been aired and assessed. Anyone with trouble breathing or chest pain needs medical care now, not monitoring.
Clear the air you're actively breathing
Once outdoor air is clean, flush the house: windows open, fans out. Then close up and run HVAC on recirculate with the highest-MERV filter the system accepts, plus HEPA air cleaners in bedrooms. This removes what's airborne — it does not touch what has settled.
Photograph before you wipe anything
Ash on sills, film on counters, the HVAC filter, the car outside. Two minutes of photos preserves both your health record and your insurance position. Bag the used HVAC filter instead of tossing it — it's a sample of exactly what the house inhaled.
Don't do these
Dry-sweeping or shop-vacuuming ash (resuspends fine particles — EPA warns handling wildfire ash without protection); running ozone generators in an occupied home (EPA cautions they can harm lungs at working concentrations); masking odor with heavy fragrance before anyone has assessed the source.