ConocoPhillips pleaded guilty to three breaches of the Offshore Installations (Prevention of Fire and Explosion, and Emergency Response) Regulations 1995. According to the HSE “It is only a matter of good fortune these incidents didn’t result in a serious, tragic incident”. ConocoPhillips was fined £3million (£1million for each offence) and ordered to pay costs of £159,459.
ConocoPhillips was responsible for two uncontrolled and one controlled but unexpected gas releases between 30 November and 1 December 2012.
The HSE found that the gas releases on 30 November 2012 occurred due to maintenance work to replace a gas pressure control valve on one of three gas turbines used to generate electricity for the installation.
To do this, the fuel gas pressure safety valve and a flexible hose had to be removed. There were releases of gas due to a number of deficiencies in isolation and planning. The released gas came out of an open ended pipe connected to the high pressure vent system. Due to a breakdown in communication across the five platforms of the site meant that some workers incorrectly believed the platform was gas-free. This put the lives of up to 66 workers in danger.
A loss of electrical power subsequently made the risk more severe. The court accepted that those sent to investigate were put at extreme risk of death or serious injury, as ignition of the gas would have resulted in an explosion. It is estimated around 603kg of produced hydrocarbon gas was released into the Turbine Hall during this incident.
On 1 December 2012, another gas release happened after batteries ran down. In this case, the isolation valve was closed in time. This stopped the gas accumulating in the turbine hall, which would have put workers at risk.
The HSE served ConocoPhillips with a Prohibition Notice on 13 December 2012 to prevent further dangerous gas releases. The company confirmed on 21 December 2012 that measures were put in place to prevent a repeat of the incidents.