Section 170.050 - General terms(a)Commanding Officer, Marine Safety Center (CO, MSC) means a district commander described in 33 CFR part 3 whose command includes a merchant marine technical office or an authorized representative of the district commander.(b)Commandant means the Commandant of the Coast Guard or an authorized representative of the Commandant.(c)Exposed waters means waters more than 20 nautical miles (37 kilometers) from the mouth of a harbor of safe refuge and other waters which the Officer in Charge, Marine Inspection determines to present special hazards due to weather or other circumstances.(d)Great Lakes includes both the waters of the Great Lakes and of the St. Lawrence River as far east as a straight line drawn from Cap de Rosiers to West Point, Anticosti Island, and west of a line along the 63rd meridian from Anticosti Island to the north shore of the St. Lawrence River.(e)Lakes, Bays, and Sounds includes the waters of any lake, bay, or sound, except the Great Lakes.(f)Oceans includes the waters of-(4) The Gulf of Alaska; and(5) Any other waters designated as "oceans" by the Commandant.(g)Officer in Charge Marine Inspection (OCMI) means an officer of the Coast Guard who commands a Marine Inspection Zone described in 33 CFR part 3 or an authorized representative of that officer.(h)Oil means oil of any kind or in any form, and includes but is not limited to petroleum, fuel oil, sludge, oil refuse, and oil mixed with wastes other than dredged spoil.(i)Partially protected waters means- (1) Waters within 20 nautical miles (37 kilometers) of the mouth of a harbor of safe refuge, unless determined by the OCMI to be exposed waters; and(2) Those portions of rivers, harbors, lakes, etc. which the OCMI determines not to be sheltered.(j)Protected waters means sheltered waters presenting no special hazards such as most rivers, harbors, lakes, etc.(k)Rivers means any river, canal, or any other similar body of water designated by the OCMI.CGD 79-023, 48 FR 51010, Nov. 4, 1983, as amended by CGD 88-070, 53 FR 34537, Sept. 7, 1988