re: film badges

["Sandy Perle" <sandyfl@ix.netcom.com>]

I apologize if this message has already been received. My ISP, 
Netcom, has been having its problems lately, and I have NOT seen this 
message since I sent it last night.. So, I am sending it again.
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Steven Jones stated the following:

> ALARA policy allows one to consider economics in the
> "reasonableness" part of the analysis.  When I do the analysis, I
> really struggle with spending thousands of dollars for enough leaded
> glasses to outfit everyone involved in angio, cath lab and EP cases
> to protect against a risk that has been shown to be all but
> nonexistent at doses received by such medical personnel.  Per BEIR V
> (p.363), "... the threshold for a vision-impairing cataract under
> conditions of highly fractionated or protracted exposure is thought
> to be no less than 8 Sv (ICRP 84).  This dose exceeds the amount of
> radiation that can be accumulated by the lens through occupational
> exposure to irradiation under normal working conditions and greatly
> exceeds that which is likely to be accumulated by a member of the
> general population through other types of exposure."  While I don't
> mean to criticize your decision to recommend leaded glasses, I feel
> there should be a realistic risk before spending any money on
> protection.  How have others approached this "ALARA dilemma"?

I agree with Steven on what the intent of ALARA is meant to be. Not
only is economics a consideration, so is sociological awareness. ALARA
also assumes a risk versus benefit evaluation. If there is a
reasonable minimization of risk, then one should expend $$. In the
power reactor world, there were many variables used, but the
predominant value focused on was $10,000/Rem avoided. One could say
that a rem could be saved if lead glasses were worn. On the other
hand, is there really a risk that needs to be avoided? The LDE annual
limit is 15 Rem. How many workers ever approach this value? Even if
they did, as pointed out already, the dose necessary to cause damage
is significantly higher than 15 Rem. So, from an ALARA evaluation,
based on valid data, there is no need for these glasses. One should
also consider what effect wearing lead glasses has on the wearer.
Again, in the power reactor world, there used to be a preponderance of
respiratory protection used. It is well documented that wearing a
respirator causes about 15 to 20% less productivity, meaning that the
individual was protecting their lungs from a NON-risk, and increasing
their stay time to external radiation exposure. Who was really being
protected. The NRC finally came out with the requirement for a TEDE
ALARA Evaluation, and when the external dose off-set any savings of
internal dose, respirators would not be used. NOW, very few are used
in the field. I see the same situation with lead glasses. How is the
worker affected, and, what effect does this have on the individual
undergoing the procedure ... does it cause additional dose to the
patient, due to extended fluoro time?

ALARA is important. It needs to be evaluated. But please, we need to
focus on tools and methods that do in fact reduce real risk, not just
perceived risk. What has been done in the past, for whatever reason,
should be reassessed against today's standards, and accepted risk
studies. To do so only gives credence to the perception that ALL
radiation exposure is harmful, for it is definitely not.
------------------
Sandy Perle
Technical Director
ICN Dosimetry Division
Costa Mesa, CA 92626
Office: (800) 548-5100 x2306 
Fax:    (714) 668-3149
  
sandyfl@ix.netcom.com
sperle@icnpharm.com

Personal Homepage: http://www.geocities.com/CapeCanaveral/1205

ICN Dosimetry Website: http://www.dosimetry.com

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