The UK saw a 39% rise in major offshore oil and gas leaks last year as well as an increase in serious injuries, said the UK Health and Safety Executive (HSE) as it warned companies to improve safety standards.
The HSE said provisional figures showed there were 85 significant hydrocarbon releases, which are regarded as potential precursors to a major accident, up from 61.
There were also 50 major injuries between 1 April 2009 and 31 March 2010 compared with an average of 42 serious injuries over the last five years.
HSE head Steve Walker said the challenge to improve safety will be greater as more offshore installations exceed their original design life.
For the third year running the industry recorded zero fatalities on offshore rigs, according to HSE statistics.