> They have a lifespan based on radioactive decay of the detector.
Americium-241 has a half-life of 432.2 years, while the recommendation is to replace a detector after only 10 years. But only 1.6% of the Am-241 has decayed after 10 years, so there must be other reasons for the short life span.
Americium-241 has a half-life of 432.2 years, while the recommendation is to replace a detector after only 10 years. But only 1.6% of the Am-241 has decayed after 10 years, so there must be other reasons for the short life span.