3.7 Gravity Drains of Spaces Other than Cargo Spaces
3.7.1 Gravity Drains Terminating in Machinery Space
Watertight spaces such as a steering gear compartment, miscellaneous machinery spaces, accommodations, voids, etc. may be drained to the main machinery space; all such drains are to be fitted with a valve operable from above the freeboard deck or a quick-acting, self closing valve. The valve is to be located in an accessible and visible location and preferably in the main machinery spaces.
3.7.2 Gravity Drains Terminating in Cargo Holds
When gravity drains from other spaces are terminated in cargo holds, the cargo hold bilge well is to be fitted with high level alarm.
3.7.3 Gravity Drains Terminating in a Drain Tank
Where several watertight compartments are drained into the same drain tank, each drain pipe is to be provided with a stop-check valve.
3.7.4 Escape of Fire Extinguishing Medium
Gravity drains which terminate in spaces protected by fixed gas extinguishing systems are to be fitted with means to prevent the escape of the extinguishing medium. See also 4-6-4/3.5.2.