A cheap check source for your radiation detector

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I was checking out my AN-PDR 27 today and thought you might like a tip. To verify if the scintillation detector in a beta/gamma survey meter is working you can use a coleman lantern mantle. They are impregnated with a thorium salt and work quite nicely. Don't hold them in your hand because you'll then use your hand/mouth vector and get crapped up. I keep a mantle in a Ziplock bag and it works fine. And remember, normal background radiation is about 50 clicks a minute with the head phones on.

-- nine (nine_fingers@hotmail.com), January 29, 1999

Answers

Nine, I may have spoken too soon when I answered your post below about abundant goods here in North Carolina. I haven't shopped the market yet for an AN-PDR 27.

-- Puddintame (dit@dot.com), January 29, 1999.

On my Aware Electronics RM-60, the background here runs only 12 to 18 clicks/min.-- converting on average to ~14 micro-roentgens/min. Clicks/min. relate differently to radiation flux for different detectors.

-- Tom Carey (tomcarey@mindspring.com), January 29, 1999.

50 cpm is very high for a background - unless you live in a coal mine. Check that radiac carefully.

Your comment about the mantle lanterns as a check source is correct, but don't worry about handling it - the contamination" won't come off with routine use.

-- Robert A. Cook, PE (Kennesaw, GA) (cook.r@csaatl.com), January 29, 1999.


GIven teh number of mantles I handled, toasted, removed, set up etc as a stove and lantern repair person, not to mention my own personal use, if it did, I'd glow, ands run about 60 on his meter. LOL

Chuck

-- Chuck, night driver (rienzoo@en.com), January 29, 1999.


This test will not work with all lantern mantles... for example, the Coleman Gold Top series use non-alpha-emitter yttrium as the rare earth element, instead of thorium. The cheaper brand X mantles should be plenty 'hot, though, as will any of the Aladdin mantles.

If anyone wonders, the reason for impregnating the mantles with these rare earths is so that it will be able to withstand the high (2000 F) temperatures produced when incandescing. Thorium is also used on vacuum tube filaments to add longevity - same reason.

-- Why@K? (who@knows.com), January 30, 1999.



Additional to my above post:

Be careful when handling the mantles, especially after they've been flashed off and are composed of delicate ash, as the above-mentioned thorium can do great harm if swallowed or inhaled. As an alpha emitter, if it gets lodged in your lungs or digestive tract, it will sit there for years, basically throwing rocks (electrons) at the local cells. Some of those cells may decide to become cancerous - need I say more.

BTW, touching them before flashing off will likely leave enough oil residue from your fingers to ruin the mantle when lit.

-- Why2K? (who@knows.com), January 30, 1999.


Gawd I love you guys, You're such a Plethoria of information. Yes the click count I gave was for radiacs I'd used in the NAV. With the civie versions your milage may vary. Yes when dealing with the ash it's toxic like you know what.Yes some of the coleman products will not produce a hot enough gamma/beta to charge/dicharge the tube. But I loved the intellegent input to my Tip.I'm so happy to know intellegent life still exists in the old you ess of a despite what the POLLs' say

-- nine (nine_fingers@hotmail.com), January 30, 1999.

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