IntuVue RDR-4000 Weather Radar Pilot's Guide
Appendix
D201002000008
58
Rev 1, December 2014
MAXIMUM PERMISSIBLE EXPOSURE LEVEL (MPEL)
FAA advisory circular AC 20-68B defines the method for determining
the MPEL boundary. All personnel should remain beyond the distance
indicated in the illustration below. Manufacturers are required to
calculate two distances; the MPEL boundary is determined by the
greater of these two distances. The first distance is the near field/far
field boundary which is the distance from the antenna that it takes for
the beam to form. For the RDR-4000 this distance is 14 ft
(4.27 meters). The second is the distance where the radiation level
exceeds the U.S. Government standard of 10 milliwatts per square
centimeter. For the RDR-4000 this distance is 11.8 ft (3.58 meters)
from the antenna. In TEST mode the system transmits two 550
microsecond pulses at the beginning of the test sequence and the safe
distance is 0.8 inches (2.1 centimeters) from the antenna during this
period. The safe fuel distance is 3.5 ft (1.07 meters) from the antenna.