In-Flight Radiation

[ROBBARISH@aol.com]

May I make another contribution to the in-flight radiation discussion? I 
posted the following paragraph to RADSAFE a few months ago:

>It is important to recognize that for all airline crewmembers, cosmic 
radiation exposures are well within the acceptable occupational limits of 50 
mSv (5 rem) annually. But, as was pointed out in other postings, exposures of 
5-6 mSv (500-600 mrem) per year are not unusual for many crewmembers. This 
means that in a career of 20 or 30 years, cumulative exposures greater than 
100 mSv (10 rem) are likely. I mention this because the HPS position 
statement "Radiation Risk in Perspective" considers individuals who have an 
exposure of "10 rem lifetime" to be potentially at increased risk of 
radiation-produced health effects. In other words, those of you who are 
critical of LNT projections for exposures of a few mrem might look at these 
crewmember exposures with a somewhat different perspective. My present 
concern for flight crewmembers is related to the lack of compliance by the 
aviation industry with a 1994 FAA advisory requesting that they provide 
information to these crewmembers about their radiation exposure. Unlike all 
other Federal agencies, which have made such training a requirement for 
occupationally exposed individuals working under their regulatory control, 
the FAA has left their recommendation in advisory form for the past five 
years, even though they know that it is being ignored. I don't think this is 
right, particularly for pregnant crewmembers who might exceed fetal dose 
limits if they continue to work their normal schedule.>

My concerns with this issue simply relate to a belief that these workers have 
the right to be properly informed about their radiation exposure and its 
risks (however small those risks may be) in the same way as are workers in 
all other industries.  It is we RADSAFE members who provide education and 
training to these more "traditional" radiation workers. I think this is 
important because the magnitude of the exposures to this worker group (as 
discussed in the previous paragraph) is greater than that of 95% of all other 
occupationally exposed individuals. This fact alone makes it hard to argue 
that the health physics profession should ignore workers receiving exposures 
which are higher than those received by most of our present constituency.
   
In 1990 the FAA issued an advisory circular (AC 120-52) on the subject of 
in-flight radiation exposure of crewmembers. In that FAA document, pilots and 
flight attendants were explicitly classified as radiation workers. A two-day 
symposium was held in Oklahoma City, the site of the FAA Civil Aeromedical 
Institute. Representatives of many of the world's airlines attended it; all 
major US carriers were represented. The 1994 advisory, AC 120-61, (referred 
to in the paragraph above) was specifically issued as a recommendation to all 
air carriers to educate their crewmembers about radiation because similar 
recommendations contained in the 1990 advisory were being ignored. In the 
1994 advisory circular, the FAA admitted that their motivation in issuing the 
document was their need to conform with the Presidential guidance on 
radiation applicable to all Federal regulatory agencies. However, in the five 
years since that advisory was published, no airline has provided any 
radiation training to their occupationally exposed workers; they have all 
ignored the second advisory as they did the first.

In Europe it will be a requirement of law in May 2000 that all flight 
crewmembers of the twenty-seven airlines in the EU receive radiation training 
and dose assessment. This came about because of concerns of the pilots and 
flight attendants unions which have more vigorously pursued these issues than 
have their US counterparts.
 
It has been my experience that flight attendants and pilots know virtually 
nothing about in-flight radiation. I am very surprised to hear that pregnant 
passengers are being told anything about the risks. It is certainly not the 
policy of any airline to provide such information. Also, the anecdotal 
incident described in the posting emphasized risks in the second trimester 
rather than the first. This suggests to me that it was most likely an 
individual flight attendant giving what she (or he) thought was helpful 
advice that was slightly off base. My solar flare hotline (1-877-SUNFLARE) is 
specifically intended to allow a pregnant passenger an opportunity to learn 
of the existence of a significant solar particle event with the possibility 
of postponing her travel for a few hours until the "storm" lessens in 
severity. You should be able to find more detailed comments on this subject 
in the RADSAFE archive from mid-summer when I posted a fairly detailed 
description of the service.

Finally, here are some comments with respect to frequent flyers. The 1 mSv 
limit for members of the public will generally be exceeded by travel of 
approximately 75,000 miles per year. There are about 400,000 business 
travelers who travel this much each year. But these are also occupational 
exposures. It is my contention that these people should also be informed 
about in-flight radiation. Even though they will never approach the 
occupational MPD as a result of their travel, I believe that they are 
entitled to the same "right to know" as are the crewmembers with whom they 
fly. Not providing this information to them could be risky. There was a legal 
conference in England last June in which British attorneys (who are far less 
litigious than their American counterparts) discussed the potential liability 
for employers who might be accused of a "failure to warn" should any of these 
business frequent-flyers develop cancer (and 22% of them will based on normal 
incidence) and decide to sue. You can read a BBC story about this at

 http://news.bbc.co.uk/hi/english/health/newsid_380000/380274.stm

By the way, I am an examiner for the ABR as was stated in a posting but I 
have not worked for the ICRP or ICRU. Perhaps the author was referring to my 
role on the program committee for the 1998 annual meeting of the NCRP on the 
topic of cosmic radiation exposure of astronauts, airline crewmembers and 
passengers.  

Rob Barish, CHP 
robbarish@aol.com
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