This International Standard specifies dimensions and materials for welding rings and drain screws situated at the bottom of oil and water tanks. Oil and water tanks occur as: — built-in tanks, as an integrated part of the hull structure, and, — detachable tanks, located in appropriate rooms and compartments. This standard covers facilities for both instances.
GSO ISO 5483:2015 history
2015GSO ISO 5483:2015 Ships and marine technology -- Drain facilities from oil and water tanks