Below bridges (BB). This term can be Found in instructions from port and charterers' agents to the ship to ensure that the ship is kept at the appropriate draft in order to ensure that it will have sufficient clearance above its highest point to pass safely below bridges (or overhead obstructions such as power cables) across a canal, channel or river in the approaches to a berth or port. To ensure the ship's clearance below bridges would be the shipowner's obligation.

 

Booking office. Conference lines, operating in certain trades, may decide to establish a booking office to take bookings and also ensure that each line carries its agreed share. Shippers may not be permitted to insist on carriage by a specific line although the booking office may try to meet shippers’ wishes in this respect as much as possible.

 

Back haul. This may be a diversion for a tanker to move cargo on the return leg of a voyage in order to minimise the ballast mileage.