(1) The ship must be proceeding en route;
(2) the oily mixture must be processed through oil filtering equipment; (3) the oil content of the effluent without dilution must not exceed 15 parts per million; (4) the oily mixture must not originate from cargo pump room bilges on oil tankers; and (5) the oily mixture, in case of oil tankers, must not be mixed with oil cargo residues. The oil filtering equipment must have an alarm to indicate when the 15 ppm level cannot be maintained, and an automatic stopping arrangement to activate in this case. (MARPOL Annex I, reg. 15. 3)
