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Radio-Frequency Radiation Hazard




Radio-frequency radiations from radar antennas and associated equipment could present a potential hazard to battery personnel. The effect of RF radiation is not cumulative, but it could be hazardous. RF radiation heats the body tissues. When the intensity is high, the radiation may produce enough heat to damage the tissues permanently. Damage to body tissue is not immediately apparent. Precautions should be taken to insure that personnel are not exposed to RF radiations of hazardous intensity levels.

A power level of 10 milliwatts per square centimeter, although not considered potentially hazardous, is stipulated by AR 40-583 as the maximum permissible exposure level for personnel subjected to RF radiation fields. Personnel should not be permitted to enter areas where they may be exposed to levels above 10 milliwatts per square centimeter.

A power density of 10 milliwatts per square centimeter is present along the axis of the transmitted beam at the following distances from the Improved Nike-Hercules radar antennas. In each instance, the intensity rapidly diminishes as the distance is increased.

                                    ANTENNA                                                                        DISTANCE

        AJI High Power Acquisition Radar Systems 502-537-Non-scanning                        240 feet   

        Systems 502-537-Rotating                                                                                        33 feet

        Systems 538-594 and 801 and above-Non-scanning                                                330 feet

        Systems 538-594 and 801 and above-Rotating                                                          60 feet

        Low Power Acquisition Radar-Non-scanning                                                            127 feet

        Missile Tracking Radar-Nike-Ajax Mode                                                                  126 feet

        Target Tracking Radar-Wide Pulse Mode                                                                  230 feet

Transmitting antennas in the non-scanning mode should not be positioned so as to radiate into areas occupied by passive antennas. The resulting reflections may present a potential hazard to personnel working in the vicinity of the passive antennas.

The intensity of the beam from the target tracking radar in the narrow pulse mode, from the low power acquisition radar when rotating, from the missile tracking radar in the Nike-Hercules mode, and from the target ranging radar is inconsequential under operating conditions.

Access to the Mobile HIPAR antenna trailer and the roofs of the equipment vans should be prohibited during periods of radar operation.

This information is base upon the average power outputs and may be used as a guide to prevent radio-frequency radiation hazards.