The tiniest spark could still cause a catastrophe on the Elgin platform, a trade union official warned last night.
With the flare now out, the most immediate threat of ignition on the stricken North Sea instillation has been removed.
But Jake Molloy, of the RMT union, says putting people on the platform when gas is still leaking would be very risky.
“There is still a significant risk there,” he said. “If you are going to go on board and work on the well in situ, then it would be a pretty risky process when the gas is still flowing out.
“Unless the gas stops flowing of its own accord, I suspect the intervention would be through a relief well.”
Mr Molloy said dropping a spanner against a piece of steel could create a big enough spark to ignite the gas.
“Tackling the leak from on board the platform would mean introducing mechanical and electrical equipment, which could spark. Even a bit of static could create a spark – it is a very volatile situation.”
Total has suspended drilling operations on two rigs in the North Sea so they can be used in a major operation to help stop the Elgin platform gas leak.
The plan, which would involve two relief wells being drilled at an installation 150 miles east of Aberdeen, is one of two now being worked as the company battles to halt the constant flow of highly flammable hydrocarbons.
The second plan is to send a crew on to the platform to carry out a “well kill” operation
Both schemes were being hampered by the flare – which is used to burn off any excess fuel or gas after a shutdown.
Drilling the relief wells could take months, but operations could start in weeks now the flare is out.
Before any drilling can be done on relief wells the seabed will have to be surveyed to see where the rig can be positioned.
Mr Molloy added: “Our main concern was getting all of the workers off – and they are all off, so it is Total’s baby now.
“All I will say is good luck to them, and I hope they can get this situation under control as soon as possible.”