Check Your Batteries Day

What the day is

Check Your Batteries Day is tied to the spring clock change, on the second Sunday of March in the United States, so the date moves. Fire services promote it because an existing twice-yearly ritual is a reliable hook for a task nobody would otherwise schedule.

Origin and background

The advice has moved on from batteries alone. A smoke alarm has a service life of around ten years, after which the sensor itself degrades and the unit should be replaced whatever the battery is doing. Most alarms carry a manufacture date printed on the back, and a great many households are running alarms well past it without knowing. Sealed units with a ten-year lithium cell are now widely recommended precisely because they remove the annual battery step and force replacement of the whole alarm on schedule.

The sensor type matters more than people realize. Ionization alarms respond faster to fast-flaming fires; photoelectric alarms respond faster to smoldering ones, which is the kind that starts in upholstery or bedding overnight and kills most often. Fire authorities generally recommend having both technologies, either as dual-sensor units or as a mix through the house.

Placement is the other half. Alarms belong on every level and outside sleeping areas, mounted on the ceiling or high on a wall since smoke rises, and kept a short distance from kitchens and bathrooms to reduce nuisance alarms, which are the main reason people disconnect them.

Two battery safety points are worth including while the drawer is open. Button cells cause severe internal burns if swallowed and are a genuine emergency, so they belong well out of reach of small children. And lithium cells should never go in household waste, where crushing causes fires in collection vehicles.

How to take part

• Check the manufacture date on the back of each alarm and replace anything near ten years old.
• Press the test button on every alarm in the house.
• Make sure you have both sensor types, or dual-sensor units.
• Take old lithium and button cells to a proper recycling point.
• Agree an escape route with the household while you are thinking about it.