Solar Radiation Alert Regions
Solar Particle Events
The map is divided into four regions based on the degree of geomagnetic shielding that air travelers
are provided by the Earth�s magnetic field. Region 1 is the polar-latitude region where the magnetic
field provides little to no protection from solar cosmic radiation. The highest dose rates occur in
Region 1. In the absence of a geomagnetic storm, dose rates in Region 2 will be lower than those in Region 1.
During a G5 geomagnetic storm, dose rates throughout Region 2 can be as high as those in Region 1.
In Region 3, a total dose to the conceptus that exceeds the recommended limit is possible in a 10-hour
exposure at 40- to 60-thousand feet, but dose rates will always be lower than in Regions 1 and 2. Dose
rates in Region 4 never exceed a few percent of dose rates in Region 1. In Region 4, in the 20-year period
January 1987 through December 2006, the highest 10-hour dose to the conceptus from solar cosmic radiation
at 50,000 ft was <10% of the recommended limit.
Calculate a Flight Dose Online with CARI-6
Larger version of the Solar Radiation map displayed below (PDF)
Larger version of the Solar Radiation map displayed below (MS Word)