nocturneYSK Your smoke detectors should be replaced every 7-10 years
GorkThis is only true for the Americium based smoke detectors. The newer photoelectric cell fire detectors don’t decay like Americium detectors, and as long as you replace the battery it’ll be good for however long it’s internal components (capacitors and whatnot) will last.
Technology Connections has a good video about this subject:
There are two types of smoke alarm. One of 'em ain't so good.
I was about to link to the same video. From what I remember though both types have strength and weaknesses in regards to the type of fire.