Electrical distribution board fire during diving operations

What happened?

A barge suffered a total loss of electrical power whilst air diving was in progress.
The power loss affected the barge cranes and the dive spread (launch and recovery system (LARS), chamber, and dive control).
The uninterruptible power supply (UPS) was activated for dive control and the dive was aborted.
Whilst the diver was being recovered to deck with LARS on the back-up power supply, a fire was reported in the barge engine room.
Once the diver was recovered to deck, all non-essential workers went to their stations whilst the situation was assessed and made safe.
No one was injured and no evacuation from the vessel was required.
Why did it happen?

An intermittent fault in a circuit in the engine room distribution board had been reported.
As the barge engineer started to remove the faulty breaker a short circuit was created. That caused a flash fire across the bus bar, burning all circuit breakers in that row.
No permit to work (PTW) was issued to the engineer.
Electrical lock-out/tag-out procedures were not followed – the engineer carried out multi-meter checks on the faulty breaker and put in place personal protective equipment but did not isolate the distribution board or the generator.
Simultaneous operations (SIMOPS) were being conducted with no prior communication between departments - work was ongoing on the main power supply at the same time as diving operations using the same main power supply.
What did they learn?

Workers should be informed and regularly reminded of safe systems of work.
Procedures (e.g. PTW, and lock-out/tag-out) should be followed at all times, even if it makes a task more complex and time consuming.
Improve communication and planning of SIMOPS, particularly when actions in one operation can impact another.
Ask yourself or your crew

How can we prevent something like this happening on our site?
What is the step-by-step procedure for replacing a faulty circuit breaker?
What should you do if you observe your colleagues working in an unsafe manner?
How do you know if any operations that can impact your work are being carried out simultaneously?
What is our fire emergency procedure?

Published on 01/04/21 1954 Views

A barge suffered a total loss of electrical power whilst air diving was in progress. Whilst a diver was being recovered to deck, a fire was reported in the barge engine room.

Original material courtesy of IMCA