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VDR is a ship’s equivalent to the black box of an aircraft. It records the details of an incident at sea that includes the date and time of an accident, the location of the vessel at the time of the incident as well as its speed, direction and more. The information recorded can be a valuable resource for identifying potential safety hazards and improving the operation of the ship.

In accordance with IMO regulations, the standard VDR must be able to store a variety of information. This includes the following: date, time and Coordinated Universal Time, vessel position (latitude and longitude, coordinate reference) as well as heading and velocity, audio recorded by the bridge (voice messages recorded using one or more microphones located on the bridge for recording conversations and audio alerts), Very High-Frequency Radio Communications (VHF) and radar data (a accurate reproduction of the display that is on view at the moment of recording) including rudder and engine orders, watertight door status, and accelerations.

The system consists of a concentrator, which encodes and processes data streams, sensors that feed data to the concentrator, and a final recording media (FRM) which can withstand accidents and allow retrieval of the voyage data. The FRM can be a fixed unit on the vessel, or a floating unit connected to EPIRB for early location in the event of an accident.

The most effective way to ensure the integrity of the vdr system is make its use an integral part of all bridge drills and training sessions for crews. The data saved can be used to identify areas where training is required and to improve bridge procedures and operational safety.