A total of 148 non-essential rig personnel were flown off oil giant Shell’s Nelson platform by helicopter on Tuesday.
And one of the helicopters making the transfer to an offshore accommodation unit had to make an unscheduled landing on another oil platform after a cockpit light came on.
A Shell spokeswoman yesterday described the rig incident as a “non-emergency” situation.
She said: “Shell UK Limited can confirm that there was a power outage on the Nelson platform, which is located approximately 124 miles east north-east of Aberdeen.
“Nelson was shut down for maintenance at the time and was not producing oil or gas.
“Work to restore main power on the platform continues with essential staff on board.
“As a precaution a non-emergency operation to remove staff to the nearby Borgholm Dolphin flotel was carried out yesterday.
“Personnel will be transported back to the Nelson platform or to Aberdeen over the next 48 hours as appropriate. There are no reports of any injuries as a result of this outage.
“The relevant authorities have been informed.”
Only 19 of the the 167 staff on board were left on the platform following the downmanning.
The platform was not producing oil or gas at the time of the blackout.
CHC confirmed that one of their helicopters was diverted to an Apache-operated platform in the Forties field before completing the passenger transfer.
It is understood it was not an emergency situation.
A spokeswoman for helicopter firm CHC said: “A helicopter was diverted and landed safely on the Forties Delta platform after a cockpit light was observed by the pilot.”
The power outage took place on the Nelson platform, 124 miles north east of Aberdeen, just before 6am on Tuesday.
The rig was undergoing planned maintenance when there was a loss of power at 5.50am.
RMT regional organiser Jake Molloy said yesterday that Shell had done “the right thing” in the circumstances.
He said: “Shell contacted us and gave us a briefing on this - a pre-cautionary downmanning due to a lack of power.
“This is what should be done in those circumstances.
“If there is no power for the life support services - air conditioning, lighting and such - you have got to put the guys to a place of safety - in this case the Borgholm Dolphin.
“Shell said it was hoping to get the platform up and running again as soon as possible.
“You can’t leave people on installations when you have power outages.”