Smoke, Fire & Gas Detection FAQs
How long do smoke alarm batteries last?
- 9V alkaline batteries last 12-18 months
- Lithium batteries last around 5 years (some lithium cells are also rechargeable, and when used in a mains-powered alarm may last for the entire functional lifespan of the alarm)
- Sealed lithium batteries last the lifetime of the alarm (usually 7-10 years)
Please note: the actual lifetime of your batteries depends on how often the alarms are tested or activated, as sounding the alarm draws more power than when the alarms are "waiting" to detect fire. You should also read your alarm's manual to make sure you only use the recommended types and brands of batteries, as failing to follow these instructions may cause the alarm to malfunction, not alerting you in the event of a fire, and might also invalidate the warranty.
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Reviewed: 14/09/2023 (doc:536 V1.0). Our articles are reviewed regularly. However, any changes made to standards or legislation following the review date will not have been considered. Please note that we provide abridged, easy-to-understand guidance. To make detailed decisions about your fire safety provisions, you might require further advice or need to consult the full standards and legislation.
