North Sea operators have been alerted after a faulty switch on board the Harbour Energy (LON: HBR) Solan platform led to the release of nearly half a tonne of fire suppressant gas.
In a safety alert issued to all duty holders this month, the Offshore Petroleum Regulator for the Environment and Decommissioning (OPRED) noted that more than 400kg of fluorinated gas was released when a faulty ATEX push-button switch inadvertently triggered on the installation last year.
OPRED confirmed to Energy Voice that the incident occurred in April 2022 on the Harbour Energy-operated Solan – a manned platform serving the field of the same name around 85 miles northwest of the Shetland mainland.
The incident occurred following a routine test of the on-board fire suppressant system, after which the switch in question was reset.
The system showed as healthy for 20 minutes but then activated without any input, releasing over 400kg of fluorinated fire suppressant gas to the environment.
No personnel were injured as a result.
A subsequent investigation showed a faulty switch was the causal factor in the release.
OPRED said water ingress had led to corrosion on the surfaces between the switch lid and its base.
This corrosion did not allow enough water into the system to damage the switch but degradation of an O-ring seal in the unit could result in future leaks that could ultimately affect its functionality, the report found.
A Harbour spokesperson said: “Safety is always the top priority for Harbour. Since this incident, which related to a switch failure as a result of a planned testing programme, we have carried out a full investigation both internally and with specialist contractors to determine the cause of the incident, and are now taking the necessary measures required to comply with the notice.
“This incident raised no risk of potential harm to any personnel.”
OPRED warned other operators who use call point activation switches with ATEX ratings – a designation for equipment used in potentially explosive atmospheres – to be vigilant.
“Duty holders who utilise such switches, particularly in systems with the potential to adversely impact the environment, should consider reviewing inspection and maintenance schedules for such switches to ensure they are sufficiently robust to minimise the likelihood of seal failure and water ingress leading to inadvertent system activation,” the regulator stated in its alert – its first such notice since 2021.
A spokesperson from the Department for Energy Security and Net Zero confirmed that: “An investigation into this incident has concluded and we are confident all the appropriate safety and environmental checks are in place.”
Brought online by Premier Oil in 2016, Solan can produce up to 35,000 barrels of liquids per day, with on board storage for up to 300,000 barrels.