[Milsurplus] TBY Radioactivity

[Ray Fantini]

Using a Ludlum model three survey meter with the Alpha head was able to pick up readings from a TBY of 20 mrem per hour that dropped to 10 mrem per hour at one foot. Perhaps all TBY are not as hot as others? Typical experience was that the level was significantly higher than radium painted interments that fall into around 2 to 3 mrem per hour and that was against the glass. Been several years ago and may have the decimal off by a place but defiantly remember the TBY that I scanned was higher reading by a factor of ten. 
 I had always figured TBY is higher due to paint being right on surface as compared to interments where you have a glass lenses that tends to block most Alpha particles. 
Have not been to concerned about the health effects, more worried EPA and a host of other state agencies. It's a long link:

http://www.mde.state.md.us/programs/researchcenter/ReportsandPublications/Pages/researchcenter/publications/general/emde/vol1no7/enforcementcompliance.aspx

But read 10848, and 5585 I do not know the amount of instruments involved but at the time they cordoned off a good part of the airport and had guys working in full protective gear, after seeing this sold off most of the aircraft instruments I had at Hamfest and checked what was left to see if anything showed up.
Ray F.




-----Original Message-----
From: milsurplus-bounces at mailman.qth.net [mailto:milsurplus-bounces at mailman.qth.net] On Behalf Of David Stinson
Sent: Monday, June 20, 2011 9:02 AM
To: milsurplus at mailman.qth.net
Subject: [Milsurplus] TBY Radioactivity

Saw someone asked about this.  Radiation is like fire; you don't run
screaming from a single lit match, but you had better from a forest 
fire.

I have a first-run TBY (no number) and finally got it out with my 
counter.
Full contact against the face panel reads just under .1 milliREM/hr.
This is a match.  A wet match.
At two feet, it is essentually background.
I have a stack of aircraft panel instruments that is much hotter.

To put this in perspective:
In order for the average person to show any effect from
a short (less than hours) exposure to a radioactive source,
they would need to absorb about 100 REM.  This is evident
by a rise in white blood cell count.  Near 100% of people
will recover fully without further complications.
When speaking of what we call "prompt" or short-term exposures,
it takes much higher levels to get into injury and mortality.
The TBY emits one one-thousandths (.0001) of this level,
meaning you would have to put the panel up against your
skin for 41+ days to accumulate this dose in the small
exposed area.  No cause for worry as long as
the radium paint stays put and is not inhaled.
I've written before on how to fix that problem.
I believe it's been published on the net
by one of our kind members.

73 Dave S.