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)