This standard applies to audible danger signals in working places and to signal systems which produce those emergency signals. It defines tests and technical requirements of safety, especially audible parameter for unified emergency signals. The signal should call all people in the reception area to attention and should request them to leave the danger area. This standard does not apply to warning and danger signals with regard to speech communication. The document does not contain specific regulations, e. g. for the public emergency management, the public traffic, for electrical audible signal devices used by the navy.