Shell has cut output at its Brent Charlie platform in the North Sea following a hydrocarbons leak detected on 30 September.
Shell was issued a prohibition notice from the Health & Safety Executive (HSE), the UK's safety regulator, following an inspection on 2 October, upstreamonline.com reported.
The notice refers to the hydrocarbon release from the platform's heating ventilation air conditioning (HVAC) system in one of the platform legs, which could not remove gas as it was supposed to.
A Shell spokesman said that problems with the HVAC system had already been identified prior to the leak and a work programme to repair the issues would start in 2010.
In order to comply with the notice, output has been decreased to the minimum required to sustain power generation on the platform while repair work is carried out.
Shell said that HSE has consented to the company running the platform at decreased production while a repair plan is drafted and executed with HSE's approval.
Brent Charlie's average output was 26,000 barrels of oil equivalent per day, including output from the Penguin field, which has also been shut down, upstreamonline.com reported.