FAA CARI Program

[ROBBARISH@aol.com]

Greetings, 

I am amazed that following my posting of last Monday, 9 August 1999 (Radsafe 
Digest 2572), much of which is reproduced below, no one has apparently taken 
the challenge of putting themselves in the position of the young flight 
attendant interested in learning her occupational dose using the CARI 
program. At least if any of you have done so, you haven't commented on the 
experience here. As you will read (reread) below, it is the official position 
of the FAA that using CARI is the appropriate thing to do if you are an 
airline crewmember.

In response to Kim Merritt's appeal for appropriate subjects for radiation 
detector R&D, let me state with certainty that an in-flight radiation 
detector capable of appropriately deriving dose equivalent values for the 
airliner cosmic radiation environment is a highly desirable project. The 
"Total Dosimeter" concept of Battelle which has been used for instrumentation 
supplied to NASA, OSHA, and the Canadian Military College needs to be taken 
to the next generation. This TEPC was mentioned in an earlier posting in 
response to my query about current instrument development. Surely we would 
all agree that having a single instrument on the flight deck which is reset 
to zero prior to departure and reads the accumulated dose upon landing is a 
much more rational system than CARI. The problem to date has been the 
difficulty of unfolding the complex secondary spectrum in an airplane and 
appropriately converting the ionization pattern to dose equivalent.

<excerpt from 2572 begins>
Regarding David's impression that dose monitoring of flight crews is of 
concern to me, it is fair to say that it is the lack of education of this 
worker group that is of far greater concern. I am not really as bothered by 
failure to institute dose monitoring (except for pregnant crewmembers) as I 
am by the failure of the FAA to require their regulated employer group (the 
airlines) to even mention this subject to the flight attendants and pilots. 

As I said earlier, the advisory circular AC 120-61 on crewmember training is 
completely voluntary, and no airline has chosen to follow its advice and 
institute such training I think this is regrettable. As I also said in an 
earlier posting, a dose of 5-6 mSv (500-600 mrem) per year for a twenty or 
thirty year career will bring the accumulated lifetime dose to these people 
above the "10 rem lifetime" dose that the HPS considers a boundary of concern 
for real health risks. As David implied later in his note, failure to 
regulate, even at the level of providing some basic educational material for 
this large worker group, is certainly out of whack with respect to the 
elaborate radiation training programs in current practice for workers 
receiving a small fraction of crewmembers doses.

Let me again state unequivocally that the FAA has classified their regulated 
constituency, flight crewmembers, as radiation workers. The have advised that 
the employers educate them with AC 120-61.  They feel that their creation of 
the CARI computer program, which is accessible to anyone who is interested, 
should serve as the mechanism for dose assessment for any interested 
crewmember. I can state this latter claim to be factual since I am in 
possession of a letter from Thomas E. McSweeny, Associate Administrator for 
Regulation and Certification of the FAA, dated 16 July 1999, in which he 
states: "The agency has also made available educational materials and a 
computer program that permits crewmembers to calculate their personal 
radiation exposure. While there is an increased risk for cancer from any 
ionizing radiation exposure, air carrier crewmembers are unlikely to exceed 
the recommended exposure limits of the Environmental Protection Agency 
because of cosmic radiation. Only pregnant flight attendants could approach 
these limits but the use of exposure calculations combined with appropriate 
flight scheduling can effectively mitigate the risk."

At this point it is appropriate to allow you all to download the famous CARI 
program in its latest version so that you can see how the agency expects the 
worker to perform these "exposure calculations." After you do so, imagine 
that you are a 20-year-old flight attendant who is interested in determining 
her dose. See what the FAA expects her to do on her PC. By the way, once you 
log on don't forget to look up the appropriate heliocentric potential from 
the FAA web site, because the program won't run without it. Go to:
www.cami.jccbi.gov and give yourself a thrill.

Addressing David's last point, about ALARA, as I said in one of my earlier 
postings, no flight crewmember is likely to exceed the 50 mSv (5 rem) annual 
dose limit. This is the limit referred to by Mr. McSweeny in the quote above. 
As far as I am concerned, receiving these occupational exposures, with their 
potential for a lifetime accumulation greater than 100 mSv, is best left to 
the crewmembers themselves but such a decision cannot be made without some 
understanding of the subject and discussion of the risks. That's where the 
current situation is so unfortunate. A large body of workers regularly 
receives these occupational exposures, and they are completely unaware of the 
situation and therefore unable to make an informed decision as to the 
acceptability of the risk. Even if all of us agree that the risk is small, we 
should also agree that these people have the right to decide for themselves 
if it is acceptable.  
<excerpt from 2572 ends>

Rob Barish
robbarish@aol.com
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