Re: Dose received from air travel?

[Bruce Pickett <SHEA136@KGV2.bems.boeing.com>]

 >They are saying that Oklamona city at 39,000 ft is only 11% less than being
 >over the poles???  I wonder if they get Northern lights there too?

 >Radiation Protection, Ministry of Health, British Columbia

 BTW, to the person in the BC Ministry of Health, your name never gets
 attached to the messages you post to RADSAFE, so I don't know who you are.

 The FAA report I quoted earlier, "Radiation Exposure of Air Carrier
 Crewmembers II," also states:

 "The earth's magnetic field (geomagnetic field) provides some shielding from
 incoming cosmic radiation particles.  The shielding is greatest over
 geomagnetic equator (near the geographic equator) and decreases to zero as
 one approaches the north or south polar regions.  Thus, at a given cruise
 altitude, the galactic radiation dose-rate increases with distance north or
 south of the equator until it reaches a plateau at high latitudes.  In the
 northern hemisphere, at a constant altitude, the galactic radiation level
 shows little or no increase above about 50 degrees geographic latitude in
 North America and 60 degrees in Europe and Asia.  Radiation levels over the
 polar regions at air carrier cruise altitudes are about twice those over the
 equator at the same altitudes (table 1)."


 Bruce Pickett
 The Boeing Company, Seattle, WA
 shea136@kgv2.bems.boeing.com

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