Shared Learning - Leak Sealing

What happened?

An employee working at a nuclear facility performing a drill and tap injection on a check valve hinge pin cover gasket injected more compound than was allowed by the procedure.

What went wrong?

The technician injected the allowed amount of compound by procedure but the check valve hinge pin cover gasket continued to leak. During the injection the technician noticed compound extruding from the gasket area due to the high pressure. The technician calculated how much extruded and determined he could inject more compound. The technician injected an additional two sticks without stopping to discuss this with the customer. The additional 2 sticks were more than were allowed by procedure to stop the leak. This could have resulted in damage to plant systems or increased the risk for injury.

Investigation Results

Root Causes
    Technician did not stop after the maximum amount of compound allowed was injected.

    Pre-job planning did not address how to proceed if the leak was not stopped as expected.

                                         How do we prevent it from happening again?

Always follow the written procedure. If the job requires any deviation from the planned activity or the technician’s sense a change in the job is needed then it has to be STOPPED and the issues addressed with the customer. Do NOT continue until all changes and concerns have been addressed and resolved.  

What actions do I take?

                  We need to be aware of the task at hand and always follow procedures.

                                         Review this Shared Learning with all employees