1. This Part of the NES provides guidance information and specifies the common design requirements for hydraulic systems in HM Surface Ships and Submarines .

2. It covers those aspects which must be considered during the system and equipment design stages: personnel and equipment safety ; prevention of fire risks ; the environmental conditions in which the systems and equipments are to operate and remain functional ; contamination control and flushing ; testing; installation; preservation .

3 . The Annexes detail the design requirements for : fire resistant hydraulic fluid OX 40 ; weapon system hydraulics, minimum flow rates for flushing ; solvents and temporary protective coatings ; checklist for the preparation of a procurement specification (PS) .