As Høglund Marine Automation explains, LNGCs make use of some of the most complex integrated automation systems in commercial shipping.
The January/February 2018 issue of LNG World Shipping highlighted the work of SIGTTO’s Human Element Committee on LNG carrier (LNGC) cargo control room (CCR) ergonomics, with special reference to alarm-system management. This initiative was triggered by investigations into several LNGC ship-to-shore interface mishaps in recent years, which revealed that difficulties can arise in interpreting CCR screens and alarms.
The article rightly noted that LNGCs make use of some of the most complex integrated automation systems (IAS) in commercial shipping. This ties into a topic that is very important to us at Høglund Marine Automation – the need to make sure that a vessel’s automated systems enhance the operations on board, rather than create new tasks.
In this instance, current IMO guidance is not specific enough to correctly prioritise the sequence of different alarms that can occur. Variability in alarm sequencing can mean different things in different contexts and lead to misinterpretations about how cargo-handling operations are progressing.
This introduces two wider, underlying issues: IAS are often not given adequate consideration at the design stage; and many automated systems are not covered by adequate guidance to ensure their proper use in service.
Inattention to IAS detail at the design stage and the lack of proper guidance are both likely to cause problems further down the line. For LNGCs, including LNG bunker vessels (LNGBVs), it is essential that both issues be given due consideration.
A recent addition to the LNGC fleet, LNGBVs are called upon to perform a particularly intense set of cargo-handling operations. The range of subsystems that can be handled by an IAS on an LNGBV includes the following:
• the fuel gas supply system (FGSS) that provides cargo boil-off gas as engine fuel
• the alarm and monitoring of the gas containment system
• the emergency shutdown (ESD) system covering cargo-handling operations, as well as the machinery and accommodation spaces
• the gas detection system, again covering cargo, machinery and accommodation spaces
• cargo-handling and monitoring, including valves, pumps and sensors
At the start of many newbuilding projects it is often unclear as to which of these systems should be included in the integrated package. Often, the functions are divided and the basic IAS deals only with the machinery systems.
Gas containment suppliers, for example, may wish to supply their own alarm, control, monitoring and ESD systems dealing solely with the gas area. The shipbuilder may thus be required to find another IAS supplier for the gas detection and machinery shutdown systems. In such circumstances, managing and prioritising alarms is made even more difficult, as it requires co-ordination between multiple systems and data formats.
Generally, the greater the level of IAS integration at an early stage the better, not least because it makes software upgrades, replacement and fine-tuning easier and gives owners and operators a single point of contact for service.
Likewise, when it comes to interfaces and system mimics, the optimum solution is to recommend at an early stage that any shipboard system provide its data in a format with an interface that can be received by the IAS. While the various parties involved in the design and procurement of the LNGC - the owner, the yard and the naval architects - may not afford IAS the same priority as, say, the choice of a propulsion system, a solid understanding of automation at the outset will pay dividends.
SIGTTO is correct to identify an automation issue which needs more attention from all parties involved. Not only can thinking about automation simplify the crew’s response to dealing with alarms, it can also lead to increased performance, reliability and, perhaps most importantly, better access to operational data that can be used for further optimisation.
Børge Nogva is CEO of Høglund Marine Automation, a company with a focus on the development of automation and gas-handling systems for LNGCs