Please Register or Log in to view the hidden image! Unfortunatly I am no good at reading danger signs !! well I will give an example of what happend to me yesterday when I took an ionization firealarm apart and stripped the 1.0uCi of Am241 out of it so I could use it as a test source. apon measureing the ionization source on Gamma detection I ended up with a very small reading of around 145.2CPM which is almost 10x backround. Apon measureing with the beta and gamma setting about 645CPM was observed. Still a radioactive source would not have a danger sign if this was the activity... Well I soon discovered why it was so dangerous. When I set my counter to broad spectrum count a+b+y the count soared to around 18,500 CPM / 185 uSv/hr !!THIS IS REALLY DANGEROUS !!! and like plutonium Am241 is a very heavy alpha emitter. Alpha radiation is the most dangerous! Legally a person needs a licence to posess anything over 5000CPM 50uSv/hr!!