MIL-STD-398 Shields, Operational For Ammunition Operations, Criteria For Design Of And Tests For AcceptanceThis standard establishes minimum design criteria and test methods for acceptance of operational shields developed to protect personnel and assets from accidental or intentional detonation of explosives during ammunition surveillance, maintenance, modification, renovation and demilitarization operations or ammunition loading operations as defined in paragraph V1.E9.3.1.1 of DoDM 6055.09-M.

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MIL-STD-398A

3.11  Simulated operational environment.  Test environment which simulates the worst possible conditions which may be present in an ammunition operation.

3.12  Simultaneous detonation.  Detonation of separated quantities of explosives or ammunition occurring so nearly at the same time (the time in milliseconds is less than 3.2 times the cube root of the explosive weight in pounds for lateral target positions and less than 4.5 times the cube root of the explosive weight in pounds for axial target positions) that the effect on the surroundings is the same as if the several quantities were not separated and were detonated en masse.

4.    GENERAL REQUIREMENTS

4.1  Design.  Operational shields shall be designed to conform to the following requirements: When required, personnel protection must limit incident blast overpressure to 2.3 psi [15.9 kPa], fragments to energies of less than 58 ft-lbs [79 joules], and thermal fluxes to prevent the onset of second-degree burns (heat fluxes and exposure times experienced by personnel should be less than that given by the equation t=200q-1.46  where "t" is the time in seconds that a person is exposed and "q" is the received heat flux in kilowatts (kW) per m2).

4.1.1  Blast attenuation.

a.  Shields, to provide protection from accidental detonation, shall be designed to prevent exposure of operating personnel to peak positive incident pressures above 2.3 psi (15.9 kPa) or peak positive normal reflected pressure above 5.0 psi (34.5 kPa).

b.  Shields, to provide protection from intentional detonation of ammunition, shall be designed to prevent exposure of operating personnel to impulse noise levels exceeding

140 Decibels.

4.1.2  Fragmentation confinement.  Shields shall be designed to:

a.  Contain all fragmentation or direct fragmentation away from areas requiring protection.

b.  Prevent generation of secondary fragmentation within areas requiring protection. c.  Prevent movement, overturning, or structural deflections which could result in

personnel injury.

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