MIL-STD-810G covers test plans for testing environmental factors to determine material suitability in various environments. See the article MIL-STD-810G – What It Is for a quick summary.
MIL-STD-461 details the requirement for the control of electromagnetic interference characteristics of subsystems and equipment.
MIL-S-901D is a Navy test specification for shock to simulate explosions in the water next to a ship or submarine.
MIL-STD-167 is a test method standard for mechanical vibration of shipboard equipment.