Lost crane load during cargo operations

Outline:

CHIRP was amongst a list of organisations to receive a completed accident investigation report from a port authority with the sole purpose of promulgating the findings to a wider audience so more people can learn from the issues highlighted.

What the report told us:

The vessel involved was a small Lift On / Lift Off general cargo vessel engaged on a regular container  freight service. On arrival the ship had been unloaded of the containers and ‘flats’ (see photo below) destined for the port and back loading was in progress. The lower level of the hold had been ‘boxed out’ with containers leaving no gaps, and the loading of flats had begun. As normal, the flats were being placed directly on top of the containers.

With the intention of leaving no gaps, the loading of flats had started forward, working aft. The first flat, containing a red van, was landed facing astern parallel to the ships side. The next flat, containing a white van was landed athwartships. The following lift was the flat containing the 4×4 vehicle involved in the incident.

Cargo operations were being carried out by a shore crane operator and contract stevedores; no ship’s crew were involved. All personnel engaged in the loading were suitably experienced and were in date for training with regards to their respective roles, there were current certificates where applicable and all lifting equipment used was in date within a six-monthly inspection routine. A six-monthly inspection routine was carried out by a third party contractor instead of a more normal annual inspection.

The 4×4 after the incident

The 4×4 vehicle concerned had been placed on the flat and secured using tensioned webbing straps and a standard lifting plan was then used by the stevedores and crane operator.  There are normally three lifting options for such a flat bed and light vehicle combination using the shore crane and spreader bar arrangement, these involved a combination of open or safety hooks and chains, side lifting lugs or top lifting lugs with webbing slings.

In this case slings were chosen in order to avoid any risk of damage to the vehicle by chains.  Lack of space in the hold precluded the use of side lifting lugs or hooks. Top lifting lugs were therefore chosen in combination with 5m webbing slings for the vehicle lifts.

The crane pre-start-up and pre operations check procedure had been properly signed off by the crane operator.  However, unknown to anyone until after the accident, the CCTV in the crane cab, whilst working, was not recording so no direct coverage of the incident was available after the event. None of the port CCTV cameras were covering the area over the vessel’s hold (one camera covered the lift from the quay but not the lowering into the hold)

The flat involved in the incident was to be placed athwartship, parallel and close to the white van. Whilst lowering down into the hold, the forward right-hand side of the flat struck the track of the moveable bulkhead. The contact was enough for the ‘top lock’ lifting equipment to become detached. This corner then dropped, causing the second ‘top lock’ on the same side to become detached, which caused the flat to tip over. The lashings attaching the vehicle to the flat then failed, and the vehicle dropped into the hold on its roof.

In the hold was the ‘hatch man’ – in constant radio contact with the crane operator –  and two other stevedores. All were at a safe distance and no-one was harmed. No ship’s crew were in the hold.

During the investigation it was found that although care is always taken to avoid standing under suspended loads, particular care is taken by stevedores with this type of “flat” due to perceived risk with the top-lifting attachments. Such concerns had not been passed on to the management. The process for operating the top lifting lug involves inserting each corner into the socket then turning the lug through ninety degrees and manually depressing the locking bar to hold it in place as weight is taken on the strops.  If the locking bar is not fully located then, if weight comes off the lug, it would be possible for the lifting lug to rotate in the socket and for the lug to disconnect from the “flat”.  Port CCTV coverage showed that, just prior to the incident, two attempts were made to lift this particular “flat” from the quay with adjustments to the lugs being made in between.

Inspection of the flat involved showed that the top plate thickness of the lifting socket of this type of unit is (at approximately 20mm)  some 8mm thinner than the standard fittings on other more modern flats and the industry standard (approx. 28mm).  Given that the top of the plate is chamfered, only a parallel plate thickness of 8-10mm is available for the tab to connect with. This increases the risk of the tab on the lug moving enough to enable the lug to twist and disconnect especially if there was a twist in the strop. the light rain at the time may also have lubricated the surfaces.

               At≈20mm the top plate thickness was 8mm thinner than more modern “flats” & the current industry standard, ≈28mm

Chamfer on the lifting socket can be clearly seen.

CHIRP Comment:

• LoLo cargo operations are considered high intensity cargo handling and are being replaced by RoRo operations in some ports and routes. However, that option is not always suitable. Small vessels going to small ports will still be using LoLo for many years to come.
• This accident could have been avoided if just one of the many layers of risk had been rectified.
• If you are aware of an issue or potential issue don’t keep it to yourself – always tell someone. Pass it on to your supervisor, put in a Hazard Observation Card or whatever method is available to notify management. Raise it at the next safety meeting.
• If there is an issue, don’t try to work around it, address it and eliminate it for your own and everyone’s safety.
• This report clearly demonstrates why we should never stand under suspended loads.

Report Ends.