Section 2 Fire and gas alarm indication and control systems

2.1.1 This Section states general requirements for fire and gas detection alarm indication and control systems. See also Pt 7, Ch 1, 5 Protection against gas ingress into safe areas, Pt 7, Ch 1, 6 Protection against gas escape in enclosed and semi-enclosed hazardous areas and Pt 7, Ch 1, 7 Emergency shutdown (ESD) systems for requirements concerning protection against gas leakage and shut-downs for process systems and associated equipment.

NOTE

The requirements for the audible and visual presentation of alerts and indicators should be determined by reference to the IMO Code on Alerts and Indicators 2009.

2.2.1 The requirements for fire detection alarms panels and sensors are given in Pt 6, Ch 1, 2.8 Fire detection and fire alarm systems of the Rules and Regulations for the Classification of Ships (hereinafter referred to as the Rules for Ships). These Rules are also to be complied with where applicable for gas detection alarms panels and sensors and fire detection alarms panels and sensors specific to the unit’s requirements. For units containing drilling facilities, specific reference should be made to the requirements of the Chapter 9 - Fire Safety, regarding fire and gas detection. For units with liquefied gas storage in bulk and/or vapour discharge and loading manifolds/facilities, see Pt 11, Ch 13, 1.6 Gas detection.

2.2.2 Automatic fire and gas detection alarm panels and sensors that satisfy the requirements of Pt 7, Ch 1, 2.2 Fire and gas detection alarm panels and sensors 2.2.3 to Pt 7, Ch 1, 2.2 Fire and gas detection alarm panels and sensors 2.2.14 are to be fitted. Additional requirements for accommodation spaces and machinery spaces are given in Pt 7, Ch 1, 2.5 Additional requirements for accommodation fire detection systems and Pt 7, Ch 1, 2.6 Machinery space fire detection systems.

2.2.3 A fire and gas detection indicating panel is to be located at the centralised control station. A repeater panel is to be provided at a location which is readily accessible to responsible members of the crew at all times, at the fire control station, if fitted, and at, or adjacent to, the workstation for navigation and manoeuvring or the workstation for safety, on the navigating bridge, if fitted. The main panel and the fire-control station repeater are to indicate the source of the fire in accordance with arranged fire zones by means of a visual signal. Any other repeater panel(s) should indicate the general area of the fire zones affected.

2.2.4 The activation of any detector or manually operated call point shall initiate a visual and audible fire and gas detection alarm signal at the alarm and repeater panels. If the signal(s) has not been acknowledged within 2 minutes, an audible fire and gas alarm, having a characteristic tone, distinguishable from any other alarm, is to be automatically and immediately audible in all parts of the navigating bridge, if fitted, the workstations for navigation and manoeuvring, the fire control station, if fitted, all accommodation areas (with the exception, on accommodation units, of those for offshore personnel), and machinery spaces. The alarm need not be an integral part of the detection system.

2.2.6 Fire and gas detection and alarm systems are to be provided with an emergency source of electrical power as required by Pt 6, Ch 2, 3 Emergency source of electrical power, and are also to be connected to the main source of electrical power, with automatic changeover facilities located in, or adjacent to, the main fire detection indicator panel, see also Pt 6, Ch 2, 1.13 Bonding for the control of static electricity. Reference should also be made to the guidance given in ISO 13702 to the supply capacity of UPS systems to defined emergency/critical facilities for the installation or unit. Failure of any power supply is to initiate an audible and visual alarm.

2.2.7 Fire and gas detectors are to be grouped as appropriate into zones conforming to passive fire protection boundaries and/or safe/hazardous area boundaries, as defined in Pt 7, Ch 2 Hazardous Areas and Ventilation. Further zones subdividing the above boundaries may also be arranged, where beneficial. Factors influencing zone boundaries include ventilation arrangements, bulkheads and the needs of the operating staff in locating and dealing with fire and gas incidents.

2.2.8 A zone/section of fire detectors which covers a control station, a service space or an accommodation space is not to include a machinery space or process area.

2.2.9 Fire and gas detection systems control and indicator panels, repeater panels, detectors heads, manual call points and short-circuit isolation units are to be suitable for their intended purpose. Detectors shall be certified by a recognised certifying authority for their intended purpose, where practicable, these should be selected from LR’s List of Type Approved Products. Other bespoke design such as control panels, etc. (see also Pt 7, Ch 1, 2.6 Machinery space fire detection systems 2.6.3) should either be certified by a recognised certifying authority for its intended purpose (where practicable, these should be selected from LR’s List of Type Approved Products) or the design appraised by Clasifications Register.

2.2.10 The fire detection system, and any associated gas detection for the accommodation spaces, as required by Pt 7, Ch 1, 2.5 Additional requirements for accommodation fire detection systems, is to be integrated with, or suitably interfaced with, the main fire and gas detection control and indication panel. Similarly, any other permanent local fire and gas detection system is to be integrated with, or suitably interfaced with, the main fire and gas detection control and indication panel. Integrated systems should not result in reducing the integrity of the individual functions.

2.2.11 When it is intended that a particular loop or detector is to be temporarily switched off, reactivation need not be automatic after a preset time provided alternative acceptable means are in place to ensure re-activation has been successfully carried out.

2.2.12 Fire detector heads for the process and wellhead area, fusible plugs and linear electric elements for direct actuating of the deluge system may be used to supplement the automatic fire detection system.

2.2.13 Gas detectors are to be selected having regard to the flammable and/or toxic gases potentially present in each particular area or compartment and are to be sited having regard to the probable dispersal of the gas as governed by density, HVAC air flows and possible points of leakage, see also Pt 7, Ch 1, 5 Protection against gas ingress into safe areasand Pt 7, Ch 1, 6 Protection against gas escape in enclosed and semi-enclosed hazardous areas.

2.2.14 Means are to be provided so that the sensitivity of gas detectors can be readily tested in their mounted positions by the injection of span gas or other equivalent method.

2.2.16 A suitable fixed hydrocarbon gas detection system for adjacent ballast tanks and void spaces of double-hull and double bottom spaces adjacent to hull hydrocarbon storage tanks, including the forepeak tank and any other tanks and spaces under the bulkhead deck adjacent to these hull hydrocarbon storage tank spaces shall be fitted. The design of this fixed gas detection system shall be in accordance with the requirements of Chapter 16 - Fixed Hydrocarbon Gas Detection Systems of the FSS Code - Fire Safety Systems – Resolution MSC.98(73).

The arrangements are to comply with Pt 7, Ch 1, 2.3 Fire-extinguishing systems 2.3.2 to Pt 7, Ch 1, 2.3 Fire-extinguishing systems 2.3.10.

2.3.4 Fire pumps are to be provided with automatic and manual starting facilities on the fire and gas detection indication and control panel. Automatic starting is to be initiated by activation of fire detection heads, operation of any manual call points or reduction of pressure in the fire main. Controls which start the standby set in the event of starting or running failure of the duty set are to be provided. Safeguards required in the event of flammable gas being detected in the vicinity of the fire pump are detailed under Pt 7, Ch 1, 5.1 General requirements 5.1.9. Manual starting facilities are to be provided adjacent to all fire pumps.

2.3.7 The electrical power required for the control, indication and alarm circuits of fire doors is to be supplied from the emergency source of electrical power. See also Pt 6, Ch 2, 3.7 Alternative sources of emergency electrical power 3.7.9. The control and indication systems for the fire doors are to be designed on the fail safe principle, with the release system having a manual reset.

2.3.8 Automatic sprinkler systems are to be considered as part of the fire detection system.

2.3.9 Whenever any sprinkler comes into operation, an alarm and visual indication is to be initiated on the panels and repeaters required by Pt 7, Ch 1, 2.3 Fire-extinguishing systems 2.3.2.

2.3.11 The design of sprinkler systems is to be in accordance with Chapter II-2 - Construction - Fire protection, fire detection and fire extinction, and Chapter 8 - Automatic Sprinkler, Fire Detection and Fire Alarm Systems. The automatic alarm and detection system is to be fed by exclusive feeders from two sources of electrical power, one of which is to be an emergency source, with automatic changeover facilities located in, or adjacent to, the main alarm and detection panel.

2.4.1 Means of stopping all ventilating fans, with manual reset, are to be provided, outside the spaces being served, at positions which will not readily be cut off in the event of a fire. The provisions for machinery spaces are to be independent of those for other spaces.

2.4.2 Machines driving forced and induced draught fans, and independently driven pumps for lubricating, hydraulic or stored oil are to be fitted with remote controls, with manual reset, situated outside the space concerned so that they may be stopped in the event of fire arising in the space in which they are located.

2.4.3 Means of cutting off power to the galley, in the event of a fire, are to be provided outside the galley exits, at positions which will not readily be rendered inaccessible by such a fire.

2.4.4 Fire safety stop systems are to be designed on the fail safe principle or, alternatively, the power supplies to, and the circuits of, the fire safety stop systems are to be continuously monitored and an alarm initiated in the event of a fault. Cables are to be of a fire-resistant type, see Pt 6, Ch 2, 5.3 Isolation and switching 5.3.10 of the Rules for Ships.

2.5.1 The requirements for accommodation fire detection systems are given in Pt 6, Ch 2, 17.1 Fire detection and fire alarm systems of the Rules for Ships, which are to be complied with where applicable.

2.5.2 Additional requirements with respect to unit types as indicated in this Section should also be complied with as applicable as in Pt 7, Ch 1, 2.5 Additional requirements for accommodation fire detection systems 2.5.3 to Pt 7, Ch 1, 2.5 Additional requirements for accommodation fire detection systems 2.5.7.

2.5.3 Fire detection systems for crew accommodation spaces and accommodation spaces for offshore personnel as defined in Pt 1, Ch 2, 2 Definitions, character of classification and class notations of these Rules, and for accommodation and support units, are to comply with the additional requirements given below.

2.5.4 Where the fire detection system does not include means of remotely identifying each detector individually, a minimum of two zones/sections of detectors is to serve cabin spaces and they are to be arranged one on each side of the unit. Exceptionally, one zone/section of detectors may be permitted to serve both sides of the unit and more than one deck where it is satisfactorily shown that the protection of the unit against fire will not be reduced thereby.

2.5.5 Heat detectors used for the protection of accommodation spaces are to operate before the temperature exceeds 78°C, but not until the temperature exceeds 54°C.

2.5.6 The permissible temperature of operation of heat detectors may be increased by 30°C above the maximum deckhead temperature in drying rooms and other accommodation spaces having a normal high ambient temperature.

2.5.7 The maximum spacing of detectors in the living quarters is to be in accordance with Table 1.2.1 Maximum fire detector spacing. Other spacing complying with appropriate National Standards will be permitted.

2.6.1 An automatic fixed fire detection system is to be fitted in all machinery space (i.e. Category A and other machinery spaces). The automatic fire detection system is to meet the requirements of Pt 7, Ch 1, 2.2 Fire and gas detection alarm panels and sensors and the additional requirements of Pt 7, Ch 1, 2.6 Machinery space fire detection systems 2.6.2 to Pt 7, Ch 1, 2.6 Machinery space fire detection systems 2.6.7 are to be satisfied. These requirements are also to be applicable for units to be assigned the UMS and CCS notations, see Pt 6, Ch 1 Control Engineering Systems.

2.6.2 An audible fire alarm is to be provided having a characteristic tone which distinguishes it from other audible warnings having lower priority. The audible fire alarm is to be immediately audible at the main control station and at all repeater stations. If the alarm is not accepted within two minutes, a general alarm is to be initiated throughout the unit.

2.6.3 Fire detection control units, indicating panels, detectors, manual call points and short-circuit isolation units are to be Type Approved. Whenever practicable they should be selected from the List of Type Approved Products published by Lloyd’s Register (LR). For addressable systems, which also require to be Type Approved, see Pt 6, Ch 1, 2.9 Programmable electronic systems – General requirements.

2.6.4 When it is intended that a particular loop is to be temporarily switched off locally, this state is to be clearly indicated at the main fire detection control panel.

2.6.5 It is to be demonstrated to the Surveyor’s satisfaction that detector heads are so located that air currents will not render the system ineffective.

2.6.6 Except in spaces of restricted height and where their use is particularly appropriate, detection systems using only heat (thermal) detectors shall not be permitted.

2.6.7 For machinery spaces utilising smoke detection or a combination of smoke and heat detection, the spacing of detectors should meet the guidance given in Table 1.2.1 Maximum fire detector spacing for maximum fire detector spacing. However greater spacing of smoke and heat fire detection than that detailed in Table 1.2.1 Maximum fire detector spacing may be implemented in areas also provided with flame detector coverage.

2.7.1  An automatic fixed fire detection system is to be fitted in enclosed general spaces where a credible fire risk has been identified. The automatic fire detection system is to meet the requirements of Pt 7, Ch 1, 2.2 Fire and gas detection alarm panels and sensors, and also Pt 7, Ch 1, 2.5 Additional requirements for accommodation fire detection systems or Pt 7, Ch 1, 2.6 Machinery space fire detection systems where appropriate to the protected general space. Spaces which afford no substantial fire risk such as void spaces, sanitary spaces, etc. need not be fitted with an automatic fixed fire detection system.

2.8.1 An automatic fixed fire detection system is to be fitted in topsides utility modules where a credible fire risk has been identified. The automatic fire detection system is to meet the requirements of Pt 7, Ch 1, 2.2 Fire and gas detection alarm panels and sensors and the additional requirements of Pt 7, Ch 1, 2.8 Fire detection systems for topsides utility modules (i.e. power generation, boilers, water injection etc.) 2.8.2 to Pt 7, Ch 1, 2.8 Fire detection systems for topsides utility modules (i.e. power generation, boilers, water injection etc.) 2.8.7 are to be satisfied.

2.8.2 An audible fire alarm is to be provided having a characteristic tone which distinguishes it from other audible warnings having lower priority. The audible fire alarm is to be immediately audible at the main control station and at all repeater stations along with initiating the general alarm throughout the unit.

2.8.3 Fire detection control units, indicating panels, detectors, manual call points and short-circuit isolation units are to be Type Approved. Whenever practicable they should be selected from the List of Type Approved Products published by Lloyd’s Register (LR).

2.8.4 When it is intended that a particular detector is to be temporarily switched off locally, this state is to be clearly indicated at the main fire detection control panel.

2.8.5 If the utility module is of an open or partially open construction, flame detection is to be provided. The number and position of utilised flame detectors is to ensure an appropriate coverage of the fire risk associated with the utility module.

2.8.6 Except in enclosed utility modules of restricted height and where their use is particularly appropriate, detection systems using only heat (thermal) detectors shall not be permitted.

2.8.7 For enclosed utility modules utilising smoke detection or a combination of smoke and heat detection, the spacing of detectors should meet the guidance given in Table 1.2.1 Maximum fire detector spacing for maximum fire detector spacing. However greater spacing of smoke and heat fire detection than that detailed in Table 1.2.1 Maximum fire detector spacing may be implemented in areas also provided with flame detector coverage.

2.9.1 An automatic fixed fire and gas detection system is to be fitted in topsides hydrocarbon process modules. The automatic fire and gas detection system is to meet the requirements of Pt 7, Ch 1, 2.2 Fire and gas detection alarm panels and sensors and the additional requirements of Pt 7, Ch 1, 2.9 Fire and gas detection systems for topsides hydrocarbon process modules 2.9.2 to Pt 7, Ch 1, 2.9 Fire and gas detection systems for topsides hydrocarbon process modules 2.9.8 are to be satisfied.

2.9.2 An audible fire and gas alarm is to be provided having a characteristic tone which distinguishes it from other audible warnings having lower priority. The audible fire and / or gas alarm is to be immediately audible at the main control station and at all repeater stations along with initiating the general alarm throughout the unit.

2.9.3 Fire and gas detection control units, indicating panels, detectors, manual call points and short-circuit isolation units are to be Type Approved. Whenever practicable they should be selected from the List of Type Approved Products published by Lloyd’s Register (LR).

2.9.4 When it is intended that a particular detector is to be temporarily switched off locally, this state is to be clearly indicated at the main fire and gas detection control panel.

2.9.5 If the process module is of an open or partially open construction, flame detection is to be provided. The number and position of utilised flame detectors is to ensure an appropriate coverage of the fire risk areas associated with the process module.

2.9.6 Except in enclosed process modules of restricted height and where their use is particularly appropriate, fire detection systems using only heat (thermal) detectors shall not be permitted.

2.9.7 For enclosed process modules utilising smoke detection or a combination of smoke and heat fire detection, the spacing of fire detectors should meet the guidance given in Table 1.2.1 Maximum fire detector spacing for maximum fire detector spacing. However greater spacing of smoke and heat fire detection than that detailed in Table 1.2.1 Maximum fire detector spacing may be implemented in areas also provided with flame detector coverage.

2.9.8 The number and position of utilised gas detectors is to ensure an appropriate coverage of the hydrocarbon leak risks associated with the process module.

2.10.1 An automatic fixed fire detection system is to be fitted in drilling areas with a fire risk. This is to be supplemented with an automatic fixed gas detection system fitted in drilling areas with a gas release risk. The automatic fire and gas detection system is to meet the requirements of Pt 7, Ch 1, 2.2 Fire and gas detection alarm panels and sensors and the additional requirements of Pt 7, Ch 1, 2.10 Fire and gas detection systems for drilling areas on mobile offshore drilling units 2.10.2 to Pt 7, Ch 1, 2.10 Fire and gas detection systems for drilling areas on mobile offshore drilling units 2.10.9are to be satisfied.

2.10.2 An audible fire and gas alarm is to be provided having a characteristic tone which distinguishes it from other audible warnings having lower priority. The audible fire and / or gas alarm is to be immediately audible at the main control station and at all repeater stations along with initiating the general alarm throughout the unit.

2.10.3 Fire and gas detection control units, indicating panels, detectors, manual call points and short-circuit isolation units are to be Type Approved. Whenever practicable they should be selected from the List of Type Approved Products published by Lloyd’s Register (LR).

2.10.4 When it is intended that a particular detector is to be temporarily switched off locally, this state is to be clearly indicated at the main fire and gas detection control panel.

2.10.5 If the drilling area is of an open or partially open construction, flame detection is to be provided. The number and position of utilised flame detectors is to ensure an appropriate coverage of the fire risk areas associated with the drilling area.

2.10.6 Except in enclosed drilling modules of restricted height and where their use is particularly appropriate, fire detection systems using only heat (thermal) detectors shall not be permitted.

2.10.7 For enclosed drilling areas utilising smoke detection or a combination of smoke and heat fire detection, the spacing of fire detectors should meet the guidance given in Table 1.2.1 Maximum fire detector spacing for maximum fire detector spacing. However greater spacing of smoke and heat fire detection than that detailed in Table 1.2.1 Maximum fire detector spacing may be implemented in areas also provided with flame detector coverage.

2.10.8 The number and position of utilised gas detectors is to ensure an appropriate coverage of the hydrocarbon leak risks associated with the drilling facilities.

2.10.9 For mobile offshore drilling units reference also needs to be made to the various requirements within the 2009 MODU Code - Code for the Construction and Equipment of Mobile Offshore Drilling Units, 2009 – Resolution A.1023(26) 9.12 Flammable gas detection and alarm system and 9.13 Hydrogen sulphide detection and alarm system.

2.10.13 The hydrogen sulphide detection and alarm system is to clearly indicate where gas has been detected, with the low level alarm indication set at 10 ppm hydrogen sulphide.