This standard covers a. refrigerating and air-conditioning systems that are an integral part of the main mechanical plant of merchant@ fishing@ and seafood-processing ships and b. refrigerated seawater and brine-chilling systems that air condition and dehumidify passenger and cargo spaces@ chill or freeze perishable cargoes@ or maintain storage of chilled or frozen cargo. This standard does not cover a. details of system designs or applications; b. small@ self-contained units that are not an integral part of the ship's main mechanical plant@ such as electric water coolers@ reach-in refrigerators@ and room air conditioners; c. cargo containers with self-contained refrigerating systems; or d. liquefied gas ships. Exceptions to the literal details of this standard may be used when approved by the authorities having jurisdiction when equivalent safety@ efficiency@ and reliability are achieved. PURPOSE The purpose of this standard is to provide the minimum general requirements for the design@ construction@ installation@ operation@ inspection@ and maintenance of mechanical refrigerating and air-conditioning equipment aboard ship to permit the safe@ efficient@ and reliable operation of such systems.