Principal requirements for the system
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC/Circular.668 – Alternative Arrangements For Halon Fire-extinguishing Systems In Machinery Spaces And Pump-rooms – (Adopted on 22 December 1994)Amended by MSC/Circular.728 - Annex - Guidelines for the Approval of Equivalent Water-Based Fire-extinguishing Systems as Referred to in SOLAS 74 for Machinery Spaces and Cargo Pump-rooms - Principal requirements for the system

Principal requirements for the system

  9 The system should be capable of manual release.

  10 The system should be capable of fire extinction, and tested to the satisfaction of the Administration in accordance with Appendix B to these guidelines.

  11 The system should be available for immediate use and capable of continuously supplying water for at least 30 minutes in order to prevent re-ignition or fire spread within that period of time. Systems which operate at a reduced discharge rate after the initial extinguishing period should have a second full fire-extinguishing capability available within a 5-minute period of initial activation. A pressure tank should be provided to meet the functional requirements stipulated in SOLAS regulation II-2/12.4.1, provided that the minimum water capacity is based on the design criteria of paragraph 19 plus the filling capacity of the piping.

  12 The system and its components should be suitably designed to withstand ambient temperature changes, vibration, humidity, shock, impact, clogging and corrosion normally encountered in machinery spaces or cargo pump-rooms in ships. Components within the protected spaces should be designed to withstand the elevated temperatures which could occur during a fire.

  13 The system and its components should be designed and installed in accordance with international standards acceptable to the Organizationfootnote and manufactured and tested to the satisfaction of the Administration in accordance with appropriate elements of Appendices A and B to these guidelines.

  14 The nozzle location, type of nozzle and nozzle characteristics should be within the limits tested to provide fire extinction as referred to in paragraph 10.

  15 The electrical components of the pressure source for the system should have a minimum rating of IP 54. The system should be supplied by both main and emergency sources of power and should be provided with an automatic change-over switch. The emergency power supply should be provided from outside the protected machinery space.

  16 The system should be provided with a redundant means of pumping or otherwise supplying the water-based extinguishing medium. The system should be fitted with a permanent sea inlet and be capable of continuous operation using seawater.

  17 The piping system should be sized in accordance with an hydraulic calculation techniquefootnote.

  18 Systems capable of supplying water at the full discharge rate for 30 minutes may be grouped into separate sections within a protected space. The sectioning of the system within such spaces should be approved by the Administration in each case.

  19 In all cases the capacity and design of the system should be based on the complete protection of the space demanding the greatest volume of water.

  20 The system operation controls should be available at easily accessible positions outside the spaces to be protected and should not be liable to be cut off by a fire in the protected spaces

  21 Pressure source components of the system should be located outside the protected spaces.

  22 A means for testing the operation of the system for assuring the required pressure and flow should be provided.

  23 Activation of any water distribution valve should give a visual and audible alarm in the protected space and at a continuously manned central control station. An alarm in the central control station should indicate the specific valve activated.

  24 Operating instructions for the system should be displayed at each operating position. The operating instructions should be in the official language of the flag State. If the language is neither English nor French, a translation into one of these languages should be included.

  25 Spare parts and operating and maintenance instructions for the system should be provided as recommended by the manufacturer.


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