MARPOL Consolidated Edition 2017

Unified Interpretations - Appendix 2
Figure 10 - Calculation of PAs for double bottom tank without clearly defined turn
of bilge area - when wing tank is segregated ballast tank or void space
Centreline
Cargo tank
4------b------
Segregated ballast
tank or void space
Double bottom
If h is less than 2 m or fs, whichever is less, anywhere along the tank length,
but hdb is at least 2 m or fs, whichever is less, along the entire tank length within the width of 2b, then:
PAs = B x cargo tank length
MARPOL CONSOLIDATED EDITION 2017 161