The table provides clarity for vessels measured under both 46 U.S.C. Chapters 143 and 145, the Regulatory Measurement System (GRT) and the Convention Measurement System (GT ITC). GRT is used to determine the number of crew required.
However, in certain cases depending on voyage and vessel particulars, the Convention Measurement System (GT ITC) is applied for determining the applicable tonnage level required for MMC/STCW endorsements.
The following table is intended to compliment Marine Safety Manual Volume III, Chapter B3, Paragraph B.3. and will be included in the next update.