46 U.S.C. § 8104 — Watches

(a) A ship's owner, charterer, operator, master, or other person in charge can only let an officer take the deck watch when the ship is leaving port, or right after, if that officer has been off duty for at least 6 hours during the 12 hours before leaving.

(b) On a small oceangoing or coastwise ship (100 gross tons or less) — except fishing, fish-processing, or fish-tender vessels — a licensed officer can't be made to work more than 9 hours out of 24 while in port (including arrival day), or more than 12 hours out of 24 at sea, unless there's an emergency threatening life or property.

(c) On a towing vessel^* on the Great Lakes and connecting waters between Gary, Indiana; Duluth, Minnesota; Niagara Falls, New York; and Ogdensburg, New York — except a towing vessel operated only for fishing, fish processing, or fish tender operations, or a towing vessel engaged in salvage operations — deck or engine department workers can't work more than 8 hours in a day, or be permitted to work more than 15 hours in 24 hours or more than 36 hours in 72 hours, except in an emergency threatening life or property.

(d) On a bigger merchant ship (over 100 gross tons) — except river, harbor, non-Great-Lakes-lake, bay, sound, or canal vessels, fishing/fish-tender/whaling vessels, small fish-processing vessels (5,000 tons or less), yachts, or salvage vessels — licensed officers, sailors, and oilers must be split into at least 3 watches at sea and rotate duty. Radio officers only need to follow this if the ship employs at least 3 of them. No one in the deck or engine department can be made to work more than 8 hours a day.

(e) On ships covered by (d): a worker can't be made to switch between deck and engine department duty or work outside the department they were hired for; a worker can't be made to do unnecessary work on Sundays or on New Year's Day, July 4th, Labor Day, Thanksgiving, or Christmas while the ship is in a safe harbor, though the ship can still depart on those days; and while in a safe harbor, 8 hours (including anchor watch) counts as a full day's work.

(f) Subsections (d) and (e) don't stop the master or another officer from calling on crew when needed, even outside normal hours, for maneuvering, mooring, or unmooring the ship; work necessary for the safety of the ship, passengers, crew, or cargo; saving lives on another endangered ship; or fire, lifeboat, or other drills, in port or at sea.

(g) On a towing vessel, offshore supply vessel, or covered barge^* on a voyage under 600 miles, workers can be split into just 2 watches instead of 3. This 2-watch option also applies to offshore supply vessels of at least 6,000 gross tons, as long as the crew follows the Secretary's hours-of-service and recordkeeping rules.

(h) On a vessel covered by section 8904, someone licensed to operate a towing vessel can't work more than 12 hours in any 24-hour period, except in an emergency.

(i) Violating subsection (a) or (b) brings a $10,000 civil penalty owed to the government.

(j) If a ship violates subsection (c), (d), (e), or (h), the owner, charterer, or operator owes the government a $10,000 civil penalty, and the affected worker can leave the ship and still receive the wages already earned.

(k) On an inspected fish-processing vessel, licensed officers and deck crew must be split into at least 3 watches at sea.

(l) Unless (k) applies, a fish-processing vessel must use at least 2 watches at sea if it either started service before 1988 and is over 1,600 gross tons, or started service after 1987 and has more than 16 crew members mainly processing fish.

(m) This section doesn't apply at all to a fish-processing vessel that started before 1988 and is 1,600 gross tons or less, or started after 1987 and has 16 or fewer crew members mainly processing fish.

(n) On a tanker, a licensed officer or seaman can't work more than 15 hours in 24 hours, or more than 36 hours in 72 hours, except during an emergency or a drill. "Work" here includes administrative duties tied to the ship, whether done onboard or ashore.

(o) On a smaller fish-tender vessel (500 gross tons or less, or under 2,500 tons if trading in the Aleutians), workers must generally be split into at least 3 watches, unless the vessel already operated in that trade before September 8, 1990, or was bought for that trade before that date and entered service by June 1, 1992 — in which case 2 watches are enough.

(p) The Secretary may set watch-standing and work-hour rules for oil spill response vessels.