5.34 TANK INSPECTION AND THE DRY CERTIFICATE
When all cargo has been discharged and the tanks and pipelines stripped
to the best of the ship and crew's ability, the chief officer must request
a tank inspection by the terminal representative and the independent
If local or terminal regulations indicate that the tanks must be closed
gauged at the completion of the discharge, then the IGS pressure must
be maintained and the tanks will be measured using the portable ullaging
device. If any measurable liquid is indicated in a cargo tank, it must
also be measured for free water.
If open inspection is acceptable and requested by the terminal or the
independent inspector, then the IGS pressure must be reduced to the
point where the tanks can be opened for inspection. Only one cargo tank
at a time should be opened and the inspection hatch should be closed
and dogged immediately after the tank bottom has been sighted.
Some owners/charterer's direct the chief officer to obtain the signatures
of the terminal representative and the petroleum inspector on a 'dry
tank(s) certificate' after this inspection. The chief officer is unlikely
to succeed in this endeavour. The inspectors will normally refuse to
sign. This is understandable since the tanks are not really 'dry' within
the definition of 'free from water or liquid' and it is unreasonable
to ask an independent inspector to indicate that they are.
It would be better to request that the inspector sign a document indicating
that there is 'no pumpable cargo remaining on board', as that is really
the objective of the inspection.
The discrimination between pumpable and un-pumpable ROB must be based
on a knowledge of the trim of the ship and the elevation of the tank
suction bellmouth above the tank bottom. See section 5.35.
If the shore terminal or independent inspector will not provide a certificate
of complete discharge of the cargo, then the ship should provide its
own certificate, signed by the chief officer to attest that all pumpable
cargo has been delivered to the receivers. This certificate may be noted
with a comment that the terminal representative has refused to sign
the document on the basis that he is not authorised (or is prohibited),
to do so.