Minute 0-3: scan the sources
Check for smoke, fragrance devices, damp materials, dusty litter, dirty pet bedding, and cooking residue. Removing or correcting a source is usually more effective than asking a filter to manage it indefinitely.
Look at outdoor AQI and weather before opening windows. Ventilation helps when outdoor air is cleaner and conditions are safe; it can hurt during smoke, heavy pollen, or extreme humidity.

