Section 8 Control, alert and safety systems

8.1.1 The requirements in this Section apply to all types of tanks, machinery and equipment.

8.1.2 Control, alert and safety systems shall comply with the relevant requirements of Pt 5 Main and Auxiliary Machinery and Pt 6, Ch 1 Control Engineering Systems of the Rules for Ships.

8.2.1 Alarms, monitoring and safeguards shall be provided for fuel supply equipment and consumers as indicated in Table 1.8.1 Methanol fuel supply and storage: Alarms, monitoring and safeguards. The Tables contain the minimum list of alarms, warnings and shutdowns for a methanol-fuelled installation. Additional alarms, warnings and shutdowns may be necessary as determined by the manufacturer or installation. A warning shall be provided in the event of any shutdown.

8.2.2 Any additional alarms and shutdowns determined on the basis of the risk-based studies shall be provided as necessary, see Ch 1, 3 Risk-based studies.

8.2.3 Arrangements shall be made so that the fuel supply to the consumers can be shut off manually from any space or area containing those consumers, the engine-starting platform or any other control position.

8.2.4 A local reading pressure gauge shall be fitted between the stop valve and the connection to shore at each bunker pipe.

8.2.5 Pressure gauges shall be fitted to fuel vapour return lines and to the bunkering lines.

8.2.6 For fuel storage tanks not permanently installed in the ship, the control, alarm and safety functions shall be provided as for permanently installed fuel storage tanks.

8.2.7 As a minimum, each fuel storage tank and bilge holding tank, see Ch 1, 7.3 Drainage arrangements, shall be provided with the following monitoring. The required alarms and shutdowns are noted in Table 1.8.1 Methanol fuel supply and storage: Alarms, monitoring and safeguards:

1. vapour space pressure. Pressure indicators shall be clearly marked with the highest and lowest pressure permitted in the tank. The high pressure alarms shall be activated before the set pressures of the pressure relief valves;

2. fuel temperature;

3. liquid level.

8.2.8 The vapour space of each fuel storage tank shall be provided with a direct pressure gauge(s) which shall be located in a space that is close to the storage tank. This space shall be considered hazardous. Additionally, an indirect indication shall be provided at a machinery control station

8.2.9 Gauging devices for fuel temperature and liquid level shall be:

1. closed devices, which penetrate the fuel tank, but which are part of a closed system and keep tank contents from being released, (e.g. a remote-reading thermometer of which the sensor is installed in the tank):

2. arranged so that they can be maintained in an operational condition without the need to empty and vapour-free the tank unless two independent devices are provided;

3. capable of being function-tested, such that all elements of the level alarms, including the electrical circuit and the sensor(s) of the high level alarm and high-high shutdown, can be tested.

8.2.10 The high level alarm and independent high-high level shutdown required in Table 1.8.1 Methanol fuel supply and storage: Alarms, monitoring and safeguards shall be provided with an audible signal and visual indication when activated. The high-high set-point is to be taken from an independent sensor and shall actuate a shut-off valve in a manner that will both avoid excessive fuel pressure in the bunkering line and prevent the tank from becoming liquid full, see also Ch 1, 6.2 Methanol bunkering system 6.2.2. Indication shall be provided at the location referred to in Ch 1, 6.2 Methanol bunkering system 6.2.1.

8.2.11 Each fuel pump discharge line and each methanol fuel manifold shall be provided with at least one local pressure indicator.

8.2.12 Alarms shall be provided to indicate low input pressure, low output pressure, high output pressure, high output temperature and failure of operation of fuel pumps using audible signals and visual indications both on the navigation bridge and in the engine room.

8.2.13 Doors to air-locks shall be monitored. Indication shall be provided at each door, such as a flashing light either side of each door to indicate when one door is open. In addition, an alarm with an audible signal and visual indication shall be provided at the machinery control position and on the navigating bridge when both doors are opened.

8.2.14 Ventilation to, and within, air-locks shall be monitored. An alarm shall be provided, with an audible signal and visual indication at the machinery control position and on the navigating bridge on loss of ventilation.

8.2.15 Indication shall be fitted on the navigation bridge, the engine control room and the manoeuvring platform to show:

1. operational parameters of the consumer, as appropriate to the type of consumer, where single fuel engines are used; and

2. (b) operational parameters of the consumer, as appropriate to the type of consumer, and which fuel the consumer is operating on, where dual-fuel engines are used.

8.3.1 For protective measures to be taken in the event of failure of pressurisation, see Table 5 of IEC 60092-502 Electrical installations in ships- Part 502: Tankers – Special Features.

8.4.1 A permanently-installed system of methanol vapour detection providing an alarm with an audible signal and visual indication shall be fitted in:

1. all enclosed spaces containing fuel supply piping and equipment or consumers, e.g. machinery spaces, cofferdams, fuel processing rooms, valve rooms;

2. other enclosed or semi-enclosed spaces where vapours may accumulate, including bunker stations and exhaust uptakes;

3. air-locks;

4. fuel outer pipes or casing where required by Ch 1, 6.5 Methanol supply system 6.5.10 and Ch 1, 7.2 Piping design;

5. outlets of, or points within, the double-walled piping or ventilated gastight ducting as per Ch 1, 7.2 Piping design 7.2.18;

6. any spaces requiring vapour detection as identified in the risk-based studies, see Ch 1, 3 Risk-based studies.

7. vent outlet from Otto cycle engine crankcases and lubricating oil purifiers; and

8. vent outlet from Otto cycle engine cooling water expansion tank.

8.4.2 Methanol vapour detection equipment shall be designed, installed and tested in accordance with IEC 60079-29-1: Explosive atmospheres - Part 29-1: Gas detectors - Performance requirements of detectors for flammable gases and shall be suitable for the vapours to be detected. The equipment shall be self-monitoring such that failure of the control panel, detector heads or sampling unit provides an alarm with an audible signal and visual indication.

8.4.3 The number and the positions of detection heads or sampling heads shall be determined with due regard to the size and layout of the compartment, the dilution from compartment purging or ventilation and stagnant areas, and the manufacturer’s recommendations.

8.4.4 The detector or sampling heads of the vapour detection systems are not to be located where liquid can collect. Pipe runs from sampling heads are not to be led through non-hazardous spaces, except as permitted by Ch 1, 8.4 Methanol vapour detection 8.4.10.

8.4.5 Alarms from vapour detection equipment required by Ch 1, 8.4 Methanol vapour detection 8.4.1 shall initiate an audible signal and visual indication:

1. on the navigating bridge;

2. at the relevant control station(s) where continuous monitoring of the vapour levels is recorded;

3. in the bunkering control position.

8.4.6 Permanently installed vapour detection shall be of the continuous detection type, capable of immediate response. Where not used to activate safety shutdown functions required by these Rules, the sampling type detection may be accepted.

8.4.7 In the selection of detectors for locations identified in Ch 1, 8.4 Methanol vapour detection 8.4.1.(g) and Ch 1, 8.4 Methanol vapour detection 8.4.1.(h), due consideration shall be taken of temperature and humidity of the environment in which the vapour is being detected. For sampling systems, the system shall include a method to dry and cool the sampled environment to that in which methanol can be accurately detected.

8.4.8 When sampling type detection equipment is used, the following requirements shall be met:

1. the detection equipment shall be capable of sampling and analysing for each sampling head location sequentially at intervals which are as short as possible but do not exceed 30 minutes;

2. individual sampling lines from sampling heads to the detection equipment shall be fitted; and

3. pipe runs from sampling heads are not to be led through non-hazardous spaces, except as permitted by Ch 1, 8.4 Methanol vapour detection 8.4.9.

8.4.9 Sampling type detection equipment may be located in a non-hazardous space, provided that the detection equipment, such as sample piping, sample pumps, solenoids and analysing units, is located in a fully-enclosed steel cabinet with the door sealed by a gasket. The atmosphere within the enclosure shall be continuously monitored. At vapour concentrations above 30 per cent LEL inside the enclosure, the entire detection unit shall be automatically shut down, including all power to external equipment.

8.4.10 Additionally, where sampling type detection equipment is located in a non-hazardous space, the following conditions are also to be satisfied:

1. vapour sampling lines shall have shut-off valves, or an equivalent arrangement, to prevent cross-communication with hazardous spaces; and

2. exhaust vapours from the detector shall be discharged to the atmosphere in a safe location.

8.4.11 Detection equipment shall be designed so that it may be readily tested. Testing and calibration shall be capable of being carried out at regular intervals. Arrangements shall be made for suitable equipment and span gas for testing and calibration purposes to be carried on board. Wherever practicable, provision shall be made for permanent connections for attachment of testing and calibration equipment.

8.4.12 Detection system(s) shall be suitable for measuring vapour concentrations of 0 to 100 per cent by volume of the LEL. Alarms shall be activated when the fuel vapour concentration reaches 30 per cent of the LEL and automatic closing of supply line master fuel valve shall occur when the vapour concentration reaches 60 per cent of the LEL. Common sampling lines to the detection equipment are not to be fitted.

8.5.1 Fire detection and alarm systems satisfying the requirements of Pt 6, Ch 1 Control Engineering Systems and Pt 6, Ch 2 Electrical Engineering of the Rules for Ships, shall be fitted in all spaces containing potential sources of fuel leakage and ignition.

8.6.1 At least two reliable and independent means of communication shall be provided for maintaining communication between the ship and the bunkering supplier during bunkering operations. Systems shall be linked ESD systems as required by Ch 1, 6.2 Methanol bunkering system 6.2.9 and comply with a recognised standard that is acceptable to LR.

8.6.2 A local pressure indicator shall be provided to indicate the pressure between the ship's manifold valves and hose connections to the bunker supply.