To stop oil leaking into any part of the boat, or overboard and causing pollution, an oil-tight tray must be fitted beneath every engine and gearbox. This will also stop oil and oil soaked debris building up within the engine space and fuelling a fire.
To prevent the oil from spreading or spilling out of the tray, the sides must be as high as practical and the tray must be made of an appropriate, non-porous material, such as metal.
A tray is not necessary if oil-tight structural members are fitted fore and aft of the engine. To reduce the chance of oil entering the watercourse and causing pollution, fixed bilge pumps must not draw from the oil tight area or tray. [2.22]