[Milsurplus] RBZ vs RBZ Special?

[John Vendely]

I rechecked the RBZ special with a TBM-3S contamination meter, and it 
measured 7.5 mR/Hr with the meter held against the side of the case.  
This would therefore be about what you'd be getting while holding the 
unit in your hand, or resting it in your lap.  The stock RBZ was hotter 
at about 10 mR/Hr.  The reading didn't get down to background level 
until the meter was three feet away.  My unit does not have the beta 
shield, so I can't be sure what kind of radiation predominates.  It 
would appear that some RBZ sets have a heavy dose of radium paint, while 
others may not.

These levels are not trivial, and indicate a significant amount of 
radium on the dials of these particular units.  It is entirely possible 
to ingest a dangerous amount of the stuff with careless handling while 
working inside the set.

Of course, we all know that Real Men scoff at such "exaggerated fears", 
but I sure as hell wouldn't mess around inside one of these things 
without first checking it, and then taking the appropriate precautions...

73,

John K9WT

On 9/17/2013 2:39 PM, Mike Morrow wrote:
>> I passed a radiac set over my RBZ and RBZ Special and was shocked
>> to discover how "hot" they are
> Got any numbers (mR/hour)?  Gamma, beta, alpha?  I don't have a alpha-
> or beta-sensitive radiac.  My gamma-sensitive radiac indicates nothing
> from my two RBZ units, case off, probe held next to the dial rotor.  I
> used an AN/PDR-27, the same type of standard portable radiac used by
> operators in the US Navy's nuclear propulsion program.
>
> Alpha radiation, if present at all, can not penetrate the RBZ casing (even
> if the case were made from a sheet of paper).   Beta radiation would be
> extremely attenuated by the plastic casing.  The only radiation of concern
> is gamma radiation, which is very penetrative even through lead.  I detect
> no gamma.
>
>> The horror, the horror...
> ...of exaggerated fears. :-)
>
> Mike / KK5F
> Military and industrial radiation worker, 1975 to 2010.
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