8 Regulation 23.8.2
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Statutory Documents - IMO Publications and Documents - Resolutions - Marine Environment Protection Committee - Resolution MEPC.122(52) - Explanatory Notes on Matters Related to the Accidental Oil Outflow Performance under Regulation 23 of the Revised MARPOL Annex I - (Adopted on 15 October 2004)Amended by Resolution MEPC.146(54) - Annex - Explanatory Notes on Matters Related to the Accidental Oil Outflow Performance under Regulation 23 of the Revised MARPOL Annex I - Part B - Guidance on Individual Regulations - 8 Regulation 23.8.2

8 Regulation 23.8.2

  8.1 Compartment boundaries Xa, Xf, Zl, Zu and y shall be developed as shown in the figures below. The shaded region represents the cargo tank under consideration.

Xa = the longitudinal distance from the aft terminal of L to the aft most point on the compartment being considered;
Xf = the longitudinal distance from the aft terminal of L to the foremost point on the compartment being considered;
Z1 = the vertical distance from the moulded baseline to the lowest point on the compartment being considered;
Zu = the vertical distance from the moulded baseline to the highest point on the compartment being considered. Zu is not to be taken greater than Ds; and
y = the minimum horizontal distance measured at right angles to the centreline between the compartment under consideration and the side.

Definition of Xa and Xf (Profile-looking inboard)

Zu, Z1 and y for outer cargo tank (Section looking forward)

Zu, Z1 and y for outer centre cargo tank (Section looking forward)

 An example showing how to measure y, in particular for a mid-deck tanker, is shown below. y shall be measured at the position above 1.5h, where h is defined as per paragraph 2.2 of regulation 19 of the revised MARPOL Annex I.

Zu, Z1 and y for mid-deck cargo tank (Section looking forward)

Parent topic: Part B - Guidance on Individual Regulations
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