The Question: I am an element that was first produced in the 1940's. This element decays by both alpha and gamma which poses serious safety issues when handling large quantities. However, this element is considered an inexpensive radiation source for portable gamma radiography of welds and as a thickness gauge in the manufacture of glass. The alpha radiation characteristics provide an ionization source for smoke detectors. A typical household smoke detector contains 200 ug of this element. What element am I? The Answer: The element is Americium (Am). The US Government nuclear fuel reprocessors sell AmO2 to licensed commercial users at $1500 per gram. In a smoke detector, the AmO2 alpha particles ionize the air in the detector, allowing a continuous current flow through the detection chamber. Smoke particles entering the space between the chamber's electrodes absorb much of the alpha radiation reducing the ionization of the air thus changing the current flow causing the alarm to trigger. The radiation dose to users of AmO2 smoke detectors is near zero because the detector case absorbs the alpha rays and the gamma ray intensity is quite low. The winner of the quiz was Bev Christian of RIM. However, the Friday Element Rules Committee does not allow Clumpy to visit the same company more than once (sorry Bev, you'll need to file a 2345678B form with the committee for an appeal) so Clumpy is now headed to visit Ian Fox, Goodrich, for his next weekly assignment. How the heck he is driving the mower over the Atlantic ocean is beyond me. Clumpy's task accomplishments: Week 1 - accomplished nothing Week 2 - conducted REACH material testing Week 3 - Solderability testing Dave Hillman Rockwell Collins [log in to unmask] ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------