Winter is statistically the most dangerous time for home fires due to increased use of space heaters, fireplaces, and furnaces. Your detectors are your first line of defense.
The Monthly Test: Don't just assume the little green light means it's working. Press and hold the "Test" button until the alarm sounds. It's a 30-second drill that could save your life.
The Battery Mission: If you didn't change your batteries in the fall, do it now. Even hardwired units usually have a 9V backup battery.