Smoke alarms are tools that can tell if there is smoke in the air.
They work even if you can't smell smoke. A smoke alarm makes a very loud beeping noise to warn you that a fire has started. When you hear the loud noise, follow your home escape plan and get out fast. Check smoke alarms monthly to make sure they are working, and so you'll know what it sounds like when it goes off. Replace old batteries with brand new ones at least once a year.