The Failure of Chain Lever Hoists

IMCA has received a near-miss report, which shows a chain lever hoist failed to be used in a sub sea operation.
 The Chain Lever hoist had a safe working load (SWL) of 3 tonnes and was used underwater for the first time. It was reported that the Chain Lever hoist was in correct usage, loaded correctly and rigged such that it was inverted, with a load of about 2 tonnes suspended from the hook on the block casing. The weight  was subsequently removed from the hook and the unit left in hoist mode. Soon afterwards, a load was again hung off the unit and a diver later tried his best  to lower it. He switched the Chain Lever hoist to lowering mode and begin to move the lever. The free chain running through the unit as he did so the load dropped; Though not before it had  dropped about 0.75 meters, the brake eventually engaging, It then operated  satisfactorily in hoist mode. All usual safety procedures had been followed and there were no injuries or significant damage to equipment. Along with other similar chain lever hoists, the unit was withdrawn from service at once and is currently undergoing extensive tests.
 It is reminded that users should pay attention to safety procedures, the importance of risk assessments, lift plans, not working under suspended loads, avoiding single point failures and the use of secondary back-up rigging. The company warns members that no certain cause for this failure has yet been identified and to take great care when using chain lever hoists.
 Investigation continues. orientation of the chain lever hoist has not been discounted as a contributory factor while no conclusions have as yet been made. As such, Besides the  previous precautions, another company has also instructed its employees that chain lever hoist is incapable of being used in the inverted position during lifting operations; that loads should not be transferred from a chain lever hoist  direct to a crane hook or vice versa without the load first being laid down in a suitable safe and stable location; and that it is necessary for particular  attention to be paid the slack chain to ensure that the chain does not bind or catch on any part of the ratchet lever hoist or adjacent equipment, during either lifting or pulling operations.
 Alert Information
 Key safety matters and incident are been summarized by these flashes, which allowing wider dissemination of lessons from them. The information below has been provided in good  faith by members and should be reviewed individually by recipients, who will determine how they related to their own operations.
 Receiving reports from members in order to pass on information and avoid repeat incidents are decided  by the effectiveness of the IMCA safety flash system. You can think of adding  the IMCA secretariat to your internal distribution list for safety alerts and/or manually submitting information on specific incidents you consider may be relevant. 
 Plenty of other organizations issue safety flashes and similar documents which may be of interest to IMCA  members. The particularly relevant may be summarized or highlighted  here. 
 The submitting organization generates any actions, lessons, recommendations and suggestions in IMCA safety  flashes   . 
 Finally stressed, the safety of chain lever hoist should be given more attention.