This International Standard provides guidance for the planning, installation and operational testing of VDR S-VDR installations according to the electric/electronic and acoustic specifications of IMO A.861 (20), IMO MSC.163 (78) and IEC 61996 (including IEC 61996-2, Simplified voyage data recorder). These standards mainly deal with interfaces between VDR/S-VDR and external sensors, which is the main subject for technical agreements between user, shipyard, VDR/S-VDR supplier and/or sensor manufacturers when installations are planned. In addition, matters of performance test and playback are also described. Furthermore, details for checking of items related to the interfaces and the installation are introduced. This International Standard is not intended for the standardization of performance factors and functional requirements related to VDR and/or S-VDR. Hereafter, VDR means VDR and S-VDR unless specifically indicated otherwise. NOTE All text of this International Standard which is identical to that of IMO A.861, IMO MSC.163, IEC 61996 and IEC 61996-2 is formatted in italics, and the Regulation and associated performance standard paragraph numbers are indicated in brackets, where necessary.