In order to use a unified base for the application of tonnage
measurement of segregated ballast tankers, Administrations are recommended
to accept the following principles;
1 The ship is certified as a segregated ballast
oil tanker as stated in paragraph 5 of the supplement to the International
Oil Pollution Prevention Certificate and the location of the segregated
ballast tanks is indicated under paragraph 5.2 of that supplement.
2 Segregated ballast tanks are those tanks exclusively
used for the carriage of segregated water ballast, as defined in Regulation 1(17) of Annex 1 of
MARPOL 73/78. The segregated ballast tanks should have a separate
ballast pumping and piping system arranged for the intake and discharge
of ballast water from and to the sea only. There should be no piping
connections from segregated ballast tanks to the fresh water system.
No segregated ballast tank should be used for the carriage of any
cargo or for storage of ship's stores or material.
3 In the International Tonnage Certificate (1969)
under “Remarks” an entry is made for the tonnage of segregated
ballast tanks in oil tankers as follows:
"The segregated ballast tanks comply with Regulation 13 of Annex 1 of the
International Convention for the Prevention of Pollution from Ships,
1973, as modified by the Protocol of 1978 relating thereto, and the
total tonnage of such tanks exclusively used for the carriage of segregated
water ballast is ...”
The reduced gross tonnage which should be used for the calculation
of tonnage based fees is ..."
4 The tonnage of segregated ballast tanks mentioned
above should be calculated according to the following formula:
+ 0.02 log 10V (or as tabulated in Appendix
2 of the International Convention of Tonnage Measurement of
||the total volume
of all enclosed spaces of the ship in cubic metres as defined in Regulation 3 of the International Convention
on Tonnage Measurement of Ships, 1969;
total volume of segregated ballast tanks in cubic metres measured
in accordance with Regulation 6 of the
International Convention on Tonnage Measurement of Ships, 1969.