This International Standard specifies the functional requirements and recommended installation and performance tests for sound reception systems. Guidelines have been drawn up for the methods and solutions to meet the functional requirements. The requirements apply to fully enclosed bridges, and other bridges where such equipment is voluntarily installed. This International Standard specifies bridge requirements that will secure a safe and efficient lookout on those seagoing ships having a fully enclosed bridge. This International Standard will be for the design of ship bridges. It will also be useful for a) specifiers and procurers of ships and bridge equipment, and b) operators and owners for ensuring that changes made through the life of a ship still conform to its requirements.