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Diver injury using cavitation blaster

A member has reported that a diver sustained a high pressure water injection injury whilst using a recently developed 4500 psi cavitation water blaster.

Cavitation gun
Cavitation gun


Retro jet showing proximity of nozzle to end of baffle (approx 3 cm)
Retro jet showing proximity of nozzle to end of baffle (approx 3 cm)

During marine growth removal operations the diver released the trigger on the cavitation gun to reposition his body. When the diver reapplied pressure to the trigger, the cavitation gun kicked back towards the diver, causing the retro end of the gun to come into close proximity of his wrist and forearm. The retro jet subsequently caused a high pressure (approximately 1000 psi) seawater injection injury to the diver’s forearm.

The injured diver was successfully treated with antibiotics at an onshore hospital facility and did not require surgery.

The risk assessment had not highlighted the fact that the retro jet posed a high pressure injection risk to the diver.

The incident investigation discovered that the diver had not been wearing the 11 inch long butyl rubber gloves as recommended by the system manufacturer but it was unclear if wearing these would have prevented the injury.

The manufacturer has now modified the retro jet by moving the nozzle further back inside the rear baffle. The company involved will be carrying out a full examination of the modification before allowing the cavitation blaster back into use.

Members are reminded of the IMCA guidance document Code of practice for the use of high pressure jetting equipment by divers.

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