Jake Molloy, Regional Organiser of the OILC union, told STV on Monday that if reports of gas bubbling up through the water under the platform are true then the situation is likely to be "very volatile".
He said there may be a risk of explosions and of the poisonous gas hydrogen sulphide, although added that the evacuation had been quick and efficient.
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The position, posted on the British Monarchy website, pays £16,000 a year for 20 hours a week.
The parents of missing 15-year-old Bristol schoolgirl who is believed to be heading to Syria have urged her to come home.
I think it is fair to say that was the best speech I have seen David Cameron give in the decade I have been reporting on him.