Leaking oxygen valve

A member has reported an incident whereby which a diver experienced an oxygen leak from his cutting torch whilst on the seabed in around 27 msw. The leak came out of the torch handle where the oxygen valve housing and the torch handle connected.

The torch was recovered and tested on the surface, where no leaks were observed. The torch was then sent back to the diver, who once again noted a leak at depth. The torch was again recovered to the surface and the dive was terminated.

Upon further investigation it was noted that the fit-up between the oxygen valve housing and torch handle was just tight enough not to leak on the surface, but at depth the ambient pressure was enough to create an oxygen leak past the trigger/torch handle union.

The company involved has made the following recommendations to prevent recurrence:

• A leak test should be performed topside on all torches prior to placing them into service. If a leak is found, the torch should not be placed into service until the leak has been corrected;
• If a leak is found coming from the torch handle, the following steps should be taken to correct the leak:
  • Apply hand pressure to the oxygen valve housing/lever assembly as it is set into the handle and tighten one of the set screws while pressure is being applied;
  • Check to ensure that the groove on the oxygen valve housing is in line with the set screw by looking into the torch handle via the opening for the set screw that has not been reinserted, located on the opposite side of the handle.
  • Tighten the other set screw and perform a leak test on the torch. A leak test should be performed topside on all torches prior to placing them into service.
• The incident and recommendations should be communicated back to the vendors of the torches. Vendors and/or manufacturers to be asked to provide QA/QC documentation verifying that each torch oxygen valve housing has been inspected and is properly seated.