What regulations govern the discharge of gray water from ships?

The regulation that governs the discharge of gray water from ships is MARPOL Annex IV. This annex, which is part of the International Convention for the Prevention of Pollution from Ships (MARPOL), specifically addresses the prevention of pollution by sewage from ships. Gray water, which comprises waste water generated from sinks, showers, and galleys, is included under the broader definition of sewage in this context.

MARPOL Annex IV outlines the requirements for the disposal of sewage and establishes standards for the treatment of such waste before discharge into the marine environment. Compliance with these regulations ensures that the discharge of gray water and other sewage does not adversely affect water quality and marine ecosystems.

The other options, while relevant to maritime regulations, do not specifically address gray water discharges. CFR Title 33 pertains more generally to navigable waters and related topics, MARINE Code 12 is not a recognized regulation associated with gray water, and ISOG 75 doesn’t apply to these specific discharges. Therefore, MARPOL Annex IV is the key regulatory framework specifically designed to control and manage the discharge of gray water and sewage from vessels.