20 year life expectancy flashlight

Jeez, Dan, that’s some pretty ballsy DIY – using radioisotopes!  I loved my tritium-backlit watch in the 1970s.  It was always on, had no battery drain and no buttons to push.  As things got dark, you noticed the backlight.  I remember the half-life as 11 years, but Wikipedia gives a NIST value of 12.32 years.

As your next project, I want you to make a tent heater from one of those cold-war-era Cobalt-60 RTGs Russian hunters find in the woods sometimes.

I had access to several “exit” signs that used the tritium technology. 20 year life expectancy. Removed the tubes from one to make several emergency lights. I’m aware of the disposal procedures when the time comes. ;-)

http://tritiumdisposal.com/betalux-tritium-exit-sign-year-life-white-frame-green-legend-single-face-bx20wtgns-p-47.html?gclid=CNTov9nBj9ECFQO2wAod2hEAog

Is the radiation harmful to humans?

Yeah, things didn’t go well for those Russian hunters.  It might be one of those Darwin awards – if you find a really warm spot where it’s frozen all around, maybe best to leave the area?

I have heated water with sugar packet size thermite formula made special for backpacking using it with a SP600 mug.

Also used carbide for a unique way to fish ;-)

Jerry, tritium is a beta emitter so it is giving off electrons.  (It is also giving off electron antineutrinos but those interact with normal matter so little, I presume them to have few health effects.)

Cut&Paste from Wikipedia: “most beta particles can be stopped by a few millimeters of aluminum. However, this does not mean that beta-emitting isotopes can be completely shielded by such thin shields: as they decelerate in matter, beta electrons emit secondary gamma rays, which are more penetrating than betas per se. Shielding composed of materials with lower atomic weight generates gammas with lower energy, making such shields somewhat more effective per unit mass than ones made of high-Z materials such as lead.

I know the astronauts on the ISS jump into polyethylene coffins during radiation storms, apparently for that effect described in the last sentence.

I suspect the flashlight housing Dan used is PE so that’s good, although it’s thinner than what the astronauts use.  Maybe a little aluminum foil wrapped around the sides of the tritium tubes would help.  Aluminum foil would be a nice addition to the survival matches, since it has so many uses as a pot, heat reflector, signaling device, etc.

My wrist would turn a little green under the tritium-backlit watch I had 35 years ago.  I assumed (hoped?) it was due to some copper alloy in the watch case and not some exotic chemistry being kicked off by the beta or resulting gamma radiation.