Hi Solarwind, The amount of Am 241 in a smoke detector has an activity of about 1 micro Curie, approximately. 1 Curie is 37 billion decay events per second, so 1 micro Curie is about 37000 events per second. Assuming that each of these events releases 1 MeV (mega electron volt) of energy and that you could capture all of that energy and make useful electrical energy from it, and do so for all of the output particles, you only get about 4 nanoWatts of output power. So, I think it is pretty safe to assume that you cannot make a radio-isotope generator from the amount of Am 241 in one smoke detector. It could be a health hazard to play with these but they are fairly safe unless you do stupid things (like grind up the sample, eat the sample, or try to concentrate the material from many smoke detectors) The vast majority of output from Am 241 is alpha particles and these are stopped within the first few cm of air. If you ingest or inhale the sample or dust from grinding it, though, then your internal organs would be exposed to the alpha particles at very short distances and there would be a hazard. Sean On Mon, Nov 8, 2010 at 12:59 AM, V G wrote: > Just curious, > > is it possible to harvest an Am-241 module from a smoke detector and > somehow make a low power electrical generator from it? Something to > power an MSP430? > > Am-241 undergoes alpha and beta decay, but Wikipedia also says it > emits gamma radiation. Probably a health hazard to play with these > things. > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .