[ RadSafe ] ALARA

garyi at trinityphysics.com garyi at trinityphysics.com
Fri Jun 20 09:58:48 CDT 2008

ALARA is just stupid.  No doubt, people believe they are fulfulling ALARA, but does anyone 
really do it?  Or do they just reach a point where they think, consciously or not, "Thats low 
enough" and stop trying to reduce doses?

Consider bone densitometers.  The operater sits unshielded at a computer about 1 to 2 
meters from the scanner.  Is that ALARA?  Yes, the dose is very low, but ALARA does not 
care how low it is.  It does not matter.  So if it is reasonable to shield a radiographic room or 
fluoro room, why is it not reasonable to shield a DEXA unit the same way, with about 1/16" 
lead and a shielded control barrier?  If ALARA is applied consistently, then perhaps all 
medical imaging rooms should have 1/8" lead on all barriers, including floor and ceiling.

This is the bottom line.  Do we get anything from ALARA that we could not have just by 
writing clear regs?  I'm sitting here trying to think of anything at all, but I can't.  I think its 
better to just tell people what the limits are and what you expect them to do to comply with 
those limits.

Somebody might say that ALARA results in lower doses to the population.  That's probably 
true, but you could have that just by writing the dose limits lower in the regs.  And this I think 
shows why we have ALARA - because nobody in authority has the guts to say "This is safe 
enough.  This dose level is safe enough."  There are too many nuts who would froth at the 
mouth upon hearing those words applied to radiation.  

If transportation risk was made ALARA, what would that look like?  I drive a lot in my 
business. That puts myself and anybody I pass on the road at risk.  People in houses along 
my route are at risk, and I bet the risk is significantly higher than the risk to someone 
exposed to 0.1 cSv.  How about that vacation you are planning?  You mean you are free, 
legally, to put all those innocent people at risk?  Without even warning them?  OMYGOSH!

-Gary Isenhower

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