Accidents continue to happen with Life Saving Appliances (LSA) in which crew were seriously or fatally injured whilst participating in drills. Crew members are becoming increasingly apprehensive during launching and recovery exercises. This news provides a set of lessons learned from our work with LSAs.
Relevant for ship owners and managers, yards, suppliers, design offices and flag states.
Course of events
During a vessel’s stay at port in calm weather, the opportunity arises for carrying out a rescue boat drill. The launching of the rescue boat in this case took place using a davit/winch and single point suspension arrangement incorporating an on/offload release mechanism, including hook and pawl, connected to the boat. After lowering the boat to the water with three crew members on board, and after completing operating tests, the davit connecting link was attached to the hook. Retrieval of the boat commenced and when hoisted to a height about 10 metres above the sea, the boat with crew were suddenly dropped into the water.
Extent of damage
The rescue boat hull was intact, but the extent of possible damage is unknown. Unfortunately, one crew member was seriously injured and taken to hospital. On examination of the release mechanism hook, the tip was found with pieces partly broken off and the pawl deformed. It is not known if the hook and pawl damages were present before this exercise, but the vessel and its equipment were only a few years old when the incident happened.
Probable causes
As part of investigations, the checking of all loose gear revealed that the diameter of the davit connecting link was less than the recommended dimensions for the release mechanism, even though the rated safe working load was suitable. The manufacturer of the loose gear is different to that of the release mechanism and boat. The damages to the hook and pawl, combined with the smaller link size, increased the gaps between these parts that could affect the link position and cause excessive loads.
It was also clear that operating instructions for hoisting were not strictly followed by the crew, as they had not confirmed the proper placement of the davit connecting link in the hook before hoisting the boat after it was out of the water.
Recommendations
DNV GL’s lessons learned from the incident mentioned above:
- Rules and regulations
Each of the components in the combined system of davit, winch, rescue boat, release mechanism and loose gear complied with relevant LSA code regulations and were certified according to applicable codes and standards.
There are no standard fittings for survival craft installations, and information given on certificates does not include complete details for compatibility with other components. This is of significance when integrating a system compiled of several components that are supplied individually. As an immediate measure, it is recommended that an on-board control of all existing survival craft installations is carried out by competent crew to check the condition and compatibility of all lifting components. Necessary amendments identified should be implemented as soon as possible.
Some specific recommendations for the following stakeholders:
- Yard and maker
Components for an integrated system should be selected from one source, which is more effective and increases the likelihood for compatibility. A manufacturer who produces all components is also expected to have a better understanding of how they interact.
The conditions for an integrated system should be straightforward, and it is important that one party is assigned the responsibility for ensuring components match and work with one other. The physical dimensions and tolerances of components are just as important as safe working loads. - Owner
To ensure reliable and successful drills, it is imperative that all LSAs are kept in good working order and readily available for immediate use. All components must be easily accessible for inspection and maintenance according to the manufacturers’ recommendations. Crew undertaking drills, inspections, maintenance and the adjustment of LSAs and their associated equipment must be fully trained and familiar with these duties, and preferably certified by the equipment manufacturers. The training of the crew should be reassessed (see MCA reference).
There are extensive volumes of manuals with operating instructions for each component of combined systems, whereby important information must be extracted and made visible to the operator. Posters or signs shall be provided in way of survival craft and launching controls that clearly illustrate the purpose and the procedures for operating the appliance. The posters and signs should be reviewed to ensure they include and reflect all relevant instructions or warnings.
Fall preventer devices (FPD) are integrated in on-load release mechanisms. As a further simple and effective precautionary measure for inadvertent operation of the on-load release mechanism, additional strops or slings should be considered (see BIMCO reference).
References
- SOLAS III/17,19 and 20
- MCA Marine Guidance Note MGN 560 (M)
- BIMCO publication “AVOID LIFE BOAT ACCIDENTS”
Contact
- Email us at Approval, Section Fire Safety & Life-saving
- Use our office locator to find the nearest DNV GL office.