Path: csiph.com!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: John-Paul Stewart Newsgroups: comp.os.linux.misc Subject: Re: Flashlights Date: Sun, 9 Nov 2025 19:05:53 -0500 Lines: 32 Message-ID: References: <6srktlxvn8.ln2@Telcontar.valinor> <_82dnatebubDjpT0nZ2dnZfqnPSdnZ2d@giganews.com> <_82dnaRebualrJT0nZ2dnZfqnPSdnZ2d@giganews.com> <10ebv9k$1fsdl$1@paganini.bofh.team> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Trace: individual.net sk5ffRW7tbmWAPeApO/Z+ABM7b1bSlHNifq0vWwPru6oVSUdvB Cancel-Lock: sha1:nZndWPz1CrEMorQPDhtdupPIBDA= sha256:M2jdCJwwtmTR36qS135GSClDpiV/x98SXcWFnKjXRyg= User-Agent: Mozilla Thunderbird Content-Language: en-CA In-Reply-To: Xref: csiph.com comp.os.linux.misc:77221 On 2025-11-09 12:04 a.m., c186282 wrote: > On 11/8/25 07:31, Carlos E.R. wrote: >> >> Curious. A lot of the smoke detectors used in Canada use those 9V >> batteries. They seem to be mandatory. > > >   Seems like most detectors sold in USA now have >   some kind of non-replacable "10-year" battery. > >   Not sure how long the Californium in the detectors >   lasts ... it'll eventually stop making so many ions. I don't know about the ones in the USA, but here in Canada, the smoke detectors I'm familiar with have the 10 year battery built-in which corresponds to the 10 year life of whatever is in the detector itself. They're advertised as "maintenance free" with a "lifetime battery". All detectors come with expiry stickers you're supposed to put on when you install them, and you're expected to replace the whole detector every 10 years. Using a regular 9-volt battery you're supposed to replace the battery every year and replace the rest of the detector after 10. Also, the ones I've had with 10 year batteries only use the battery as backup in the event of power failure. They're hardwired to a 120 volt household circuit for primary power. There are similar hardwired ones with 9-volt backup batteries as well as models that are solely powered by the 9-volt battery for places where hardwired ones aren't viable. But in all cases smoke detectors are presumed to only be good for 10 years.