CFR › Title 46 › Part 128Part 128 — Marine Engineering: Equipment and SystemsSubpart A — General§ 128.110— Equipment and systems.§ 128.120— Plan approval.§ 128.130— Vital systems.Subpart B — Materials and Pressure Design§ 128.210— Class II vital systems—materials.§ 128.220— Class II non-vital systems—materials and pressure design.§ 128.230— Penetrations of hulls and watertight bulkheads—materials and pressure design.§ 128.240— Hydraulic or pneumatic power and control—materials and pressure design.Subpart C — Main and Auxiliary Machinery§ 128.310— Fuel.§ 128.320— Exhaust systems.Subpart D — Design Requirements for Specific Systems§ 128.410— Ship's service refrigeration systems.§ 128.420— Keel cooler installations.§ 128.430— Non-integral keel cooler installations.§ 128.440— Bilge systems.§ 128.450— Liquid-mud systems.