LTI and RWC following failure of diving bell door

摘要

An IMCA member has reported an incident in which two divers were injured following the failure of a diving bell door. The incident occurred following some bell internal maintenance and surface bell checks, when the bell was being pressurised back onto the saturation chamber system at a depth of 130 feet to allow the two divers to transfer under pressure back to the saturation chamber. It led to a lost-time incident (LTI) and restricted workday case (RWC). During final checks, dive control was informed by the life support technician (LST) that the seal between the transfer under pressure (TUP) module and the trunk was not possible as he suspected that the door was not 'dogged' tight enough shut. The divers were informed, in the bell, of the situation with the top door of the TUP and that the internal bell door would have to come back up so that the dogs on the TUP could be properly secured. Minutes later, the divers were told by the dive supervisor the bell door was about to be opened again. As the bellman was opening the bell door and was about to secure it with the safety chain, the second diver stepped on the rim of the opening before the safety chain was secured. At this instant, the door fell onto his feet. The dive superintendent was informed instantly that there had been a failure and the diver's feet were trapped.