DESCRIZIONE
A subsea assistance system for supporting saturation diver operations comprises a UUV such as an observation ROV that can be flown to a subsea worksite, and various items of ancillary electrical equipment that are connected or subsea-connectable to the UUVor to a skid forming part of the UUV. Those items may comprise any of: a hand-portable subsea display that displays an image to a diver communicated from the UUV, which image may be generated or enhanced underwater and/or by surface support; a subsea camera that captures subsea image data for communication to the UUV and from the UUV to surface support; and a selection of electrical power tools for performing subsea tasks. Fast-acting protective devices protect divers when using high-voltage wet-mateable subsea connectors on the UUV.