The agency expects that deficiencies similar to those revealed by the incident on 23 August 2008 will not create the potential for a major accident in the future.
Seventeen people at the plant near Bergen were close to the cracker when it failed, posing the risk of a fire and/or an explosion.
This incident occurred shortly before the process equipment was to be run down ahead of a two-month shutdown for a scheduled turnaround.
The only unit of its kind in Norway, the Mongstad cracker – as its name indicates – is used to crack heavier crude oil fractions into lighter hydrocarbons.
“We take a very serious view of this incident,” says Einar Ravnås, the PSA’s supervision coordinator for land-based plants.
“The cracker itself is associated with a high risk potential. But the way it was secured had clear weaknesses, which could also apply to other types of process equipment there and elsewhere.”
He emphasises the importance of both the industry and operator StatoilHydro learning the lessons from the latter’s investigation into the Mongstad incident. The PSA has held a number of meetings with the company since the event, and has carried out audits both of the refinery and the operator’s response.
“A number of deficiencies were identified,” says Mr Ravnås. “On that basis, StatoilHydro has modified the way the cracker is managed, its emergency preparedness and employee training.”