Use Environment per MIL HDBK-217F (Naval):
Naval, Sheltered: Includes sheltered or below deck conditions on surface ships and equipment installed in submarines.
Naval, Unsheltered: Unprotected surface shipborne equipment exposed to weather conditions and equipment immersed in salt water. Includes sonar equipment and equipment installed on hydrofoil vessels.
Ground Environments, Airborne Environments
Back to the Mean Time Between Failure Definition, or the Military Specifications page.
Electronic Key Words: Failure Mode Analysis, Reliability Prediction, MIL-HDBK-217, Ship, Sea, Navy, Bellcore
/ Telcordia, IEC 62380
