Section 5 General emergency alarm
Clasification Society 2024 - Version 9.40
Clasifications Register Rules and Regulations - Rules and Regulations for the Classification of Naval Ships, January 2023 - Volume 2 Machinery and Engineering Systems - Part 9 Electrotechnical Systems - Chapter 10 Internal Communication - Section 5 General emergency alarm

Section 5 General emergency alarm

5.1 Emergency alarm system

5.1.1 An electrically operated bell or klaxon or air-operated whistle with independent air supply or other equivalent warning system installed in addition to the ship’s whistle or siren, for sounding the general emergency alarm signal is to comply with the International Lifesaving-Saving Appliances (LSA) Code and with the requirements of this Section, see also Vol 2, Pt 9, Ch 3, 8.10 Cable support systems 8.10.6 and Vol 2, Pt 9, Ch 1, 2.5 Operation under fire conditions.

5.1.2 The general emergency alarm system is to be provided with an emergency source of electrical power as required by Vol 2, Pt 9, Ch 2, 5.2 Emergency source of electrical power and Vol 2, Pt 9, Ch 2, 5.3 Starting arrangements and also connected to the main source of electrical power with automatic changeover facilities located in, or adjacent to, the main alarm signal distribution panel. Failure of any power supply is to operate an audible and visual alarm, see also Vol 2, Pt 9, Ch 3, 8.10 Cable support systems 8.10.6.

5.1.3 The general emergency alarm distribution system is to be so arranged that a fire or casualty in any one main vertical zone other than the zone in which the crew and embarked personnel address control station is located, will not interfere with the distribution in any other such zone.

5.1.4 There are to be segregated cable routes to crew and embarked personnel rooms, alleyways, stairways, and control stations, so arranged that any single electrical fault, localised fire or casualty will not cause the loss of the facility to sound the general emergency alarm in any crew and embarked personnel rooms, alleyways, stairways, and control stations, be it at a reduced capacity.

5.1.5 Where the special alarm fitted to summon the crew – operated from the navigation bridge, or fire-control station, forms part of the ship’s general alarm system, it is to be capable of being sounded independently of the alarm to the passenger spaces.

5.1.6 The sound pressure levels are to be measured during a practical test and documented, see Vol 2, Pt 9, Ch 12, 1.2 Trials.

5.1.7 Sound signal equipment, fire and general alarm bells are to be supplemented by visual indications in areas having high levels of background noise, such as machinery spaces.


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