P-385-63 Range Safety Pamphlet Download
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c. Numerous health hazard assessment reports define hazardous impulse noise contours for various tank/fighting vehicle main gun and secondary armament cartridges exceeding 140 dBP. Table 8–21 summarizes these contour requirements and figure 8–14 illustrates the hazardous impulse noise contours in relation to the GTL. Double hearing protection shall be worn when exposure is expected to be in excess of the daily exposure limit. Use of double hearing protection increases the daily exposure limits as determined by The Surgeon General. Loader may not have their head protruding above the open hatch while firing the main gun. Data for locations forward of tank/fighting vehicle weapon systems are not available. Impulse noise levels in front of tank systems are expected to be higher than to the sides and rear. Table 8–21 Hazardous impulse noise contours for various tank/vehicle cannon cartridges Cartridge Caliber (mm) Distance to 140 dBP contours (meters) 90 degrees 135 degrees 180 degrees M490 105 501 NDA NDA M490A1 105 400 NDA 200 M831 120 444 314 152 M865 120 501 355 NDA M968 35 130 NDA NDA All .50 cal 32 16 NDA All 7.62 15 7 NDA Figure 8–14. Hazardous impulse noise 140 dBP contour zones 106 DA PAM 385–63 • 16 April 2014