The timing, plainly
When should you change smoke alarm batteries?
Twice a year for battery swaps — the daylight-saving clock changes are the classic anchor because they already interrupt your routine — plus a monthly test press, and replace the entire alarm every 10 years (the sensor itself wears out, sealed 10-year-battery models included). The chirp at 3 a.m. is the system working as designed; the reminder exists so you act before the chirp.
Batteries fade predictably; sensors age out at about a decade. Two recurring dates cover a life-safety device completely.
Where it sits in the year
Ordered from this month — this is the shape of it on a timeline.
Do sealed 10-year alarms need anything?
No battery swaps — but they still need the monthly test press, and the whole unit still gets replaced at the end of its rated life. The manufacture date is printed on the back.
Why does the alarm chirp at night?
Battery voltage drops slightly in cooler overnight temperatures, which is when a weak battery first crosses the low-voltage threshold. It is annoying and it means the low-battery detection works.
The date is the easy part. Remembering is the product.
Reviewal keeps windows like this on one page — the whole year of them — and emails you before each one opens. Your calendar handles what's today; this is the layer above it. Free to start: 40 events, 3 sections, reminders included.
Tracking this in a spreadsheet or calendar today? See exactly what changes: vs. a spreadsheet · vs. calendar reminders