Remaining on board
ROB
Meaning
Remaining on board (ROB) is cargo left in a tanker's tanks after discharge; on-board quantity (OBQ) is residue already in the tanks before loading.
Also written as OBQ, On board quantity
Remaining on board explained
After discharge, an independent surveyor measures what remains. If the ROB is pumpable, receivers may claim the value from the owner. Charters often require the ship to discharge to a set standard and give the owner a defence if it did.
OBQ measured before loading is deducted when comparing ship and shore figures, so cargo shortages aren't wrongly blamed on the ship.
Related terms
Crude oil washing
Crude oil washing (COW) cleans a crude tanker's cargo tanks during discharge by spraying them with the cargo itself to dislodge residues.
Cargo shortage
A cargo shortage is a difference between loaded and discharged quantities; many tanker charters let charterers deduct losses above 0.5%.
Ullage
Ullage is the empty space between the surface of the liquid cargo and the top of the tank, measured to work out how much cargo is on board.
Slops
Slops are the oily water mixtures from tank washing and cargo residues, collected in a tanker's slop tanks for disposal or for loading on top.