46 C.F.R. Subpart 3.05—Definition of Terms Used in This Part
Title 46 - Shipping
A letter issued by an Officer in Charge, Marine Inspection, designating an uninspected vessel as an oceanographic research vessel. “An oceanographic research vessel is a vessel which the U.S. Coast Guard finds is employed exclusively in one or more of the following: (a) Oceanographic instruction; (b) Limnologic instruction; (c) Oceanographic research; or, (d) Limnologic research.”
Title 46: Shipping
PART 3—DESIGNATION OF OCEANOGRAPHIC RESEARCH VESSELS
Subpart 3.05—Definition of Terms Used in This Part
§ 3.05-1 Letter of designation.
§ 3.05-3 Oceanographic research vessel.

