Grab hopper dredger Abigail H capsized and sank while alongside at the port of Heysham when her bilge flooded at night. No bilge alarm was fitted because the half-century old 34 metre long vessel fell between two sets of regulations that would have required one.
The requirement to fit bilge alarms in engine rooms exists where these compartments are periodically unattended. This is normal practice in small vessels, and the Maritime and Coast Guard’s workboat and fishing vessel codes of practice require bilge alarms to be fitted. In larger ships, unmanned machinery space, UMS, is common and modern control systems are built with this in mind; bilge alarms are required and engine room personnel must hold formal qualifications.
Says the UK’s Maritime Accident Investigation Branch:”Abigail H is one of a large number of vessels that sit between these two groups. The effect is that these relatively small vessels require no bilge alarm and are manned with engine room personnel that have not received formal training.
”There is no expectation for the engine room to remain manned when machinery
is shut down overnight, but this incident demonstrates the results of a relatively
minor leak in this type of vessel can be catastrophic if undetected.”
The need to fit bilge alarms had been
considered at least twice in the 325 tonne-vessel’s recent history but, because they were
not mandatory, was not seen as a priority.
During the subsequent MAIB investigation, a leak was found near the aft end of the engine room, close to bilge suction pipework underneath the stern gland. Although it was not possible to inspect the hull plating, analysis of the bilge systems indicates that it is most likely that the leak was caused by hull plating becoming perforated in this area.
While the flooding may have been relatively slow Abigail H was loaded with silt dredged from the outlets of a nearby power station, which reduced its reserve of stability and less flooding was needed to make the vessel become unstable.
Fortunately the vessel rolled towards, and was then supported by the jetty. If Abigail
H had rolled away from Fish Quay, it is unlikely that the mooring lines would have restrained the roll, and it is possible that the accommodation could have become submerged and the crew trapped in their cabins.
Wyre Marine Services, which owns Abigail H, has now fitted bilge alarms in the engine room and other significant compartments in Abigail H and the other three dredgers that they operate. These alarms operate from main and emergency power sources and are sufficient to alert sleeping crew and passers-by. It has also introduced fleet-wide procedures to conduct inspections of all compartments during periods when crew are asleep on board overnight as well as changing operating practices so that spoil will not be kept in the hopper overnight.
Although the vessel was relatively old, Wyre has put a great deal of effort into maintaining the condition of Abigail H and the most recent survey had found the vessel to be in a satisfactory condition.
Says MAIB: “Annex 3 of MGN 322, Ship Survey Standards (Annex A) details the information required by the MCA when it conducts surveys for the issue of statutory documents. However, it is not always practical to expect owners of vessels like Abigail H to have or to prepare much of this information. A pragmatic approach is needed in these cases, making best use of the information that is available. This should include a thorough search of the related files already held by the MCA to avoid the situation, as in this case, where potentially useful drawings were overlooked because they were stored in another office.
”The regulations for vessels greater than 24m registered length and less than 500 gross tons are complicated, and many discrete sources need to be drawn together to achieve the proper effect. This is in contrast to workboats and fishing vessels, where the regulations are presented as Codes of Practice, making the requirements clear to owners and implementation more straightforward for surveyors. It was evident that applying the appropriate regulations and explaining the requirements to Abigail H’s various owners took up a considerable amount of MCA surveyors’ time. It is an inevitable consequence that this would have put pressure on the amount of time available for detailed inspection of the vessel’s condition… It is recognised that consolidating the regulations applicable to vessels greater than 24m registered length and less than 500 gross tons into a code of practice is a substantial task, but this is a logical goal and offers multiple benefits to the MCA and owners.”
Also notable is the owner was safety-orientated: He had spent much of his career at sea in the offshore industry working on supply vessels where he had progressed to becoming a master before helping to develop safety management systems in his employer’s office ashore. He had become a partner in Wyre Marine Services in April 2007, and was applying many of the practices and procedures that he had learned in the offshore industry to the company’s vessels. These included planned maintenance, emergency procedures and, although not required by regulation, he was developing a safety management system. Wyre Marine Services had arranged sea survival, fire-fighting and first-aid courses for crew members who had not done this training previously, and all the crew involved in this accident had completed these.
However, there was no specific assessment of the risks associated with sleeping on board overnight once normal operations had finished and machinery was shut down. The checking of compartments or the safety of the moorings was left to the crew’s discretion.
Says MAIB: “A properly structured assessment of risks to crew sleeping on board a vessel that has been shut down overnight is required, and should consider, as a
• Security of moorings
• Vessel emergencies
• Noxious atmosphere (ie carbon monoxide)
• Medical casualties
• Loss of stability
• Response to actions of other vessels
• Effects of extreme weather
Many of these functions are, in larger ships, traditionally provided by personnel being on duty overnight. In smaller vessels this is not always practical and other means of achieving the same effect, which can attract the attention of sleeping crew, are needed. This should include a method of communication between the vessel and port authorities (such as a mobile telephone).”
MAC notes that, after years of few or no life-threatening incidents it is easy to become complacent. In the case of Abigail H, three of the four crew were mariners while the fourth was a dredger operator from the construction industry.
It was the dredger operator who had taken care to keep his lifejacket, torch, mobile phone and a high visibility jacket close at hand in his cabin, and grabbed them before leaving.
Evidently he had not let familiarity breed content.