The owners of Grangemouth refinery have been fined £100,000 over a spill of highly flammable oil.
Ineos pleaded guilty at Falkirk Sheriff Court to the safety breach three years ago.
In the incident, a pipeline became pressurised and sprayed crude oil across a nearby pumphouse and pipelines containing other dangerous liquids.
An investigation found the company had been aware of the risk and the need to install controls.
But it also found Ineos chose to rely on staff to reduce pressure by manually draining oil from the pipeline, and storing it in a skip that was not designed for storing oil.
In a statement, Ineos said "a small quantity" of crude oil leaked from a pipeline supplying one of the refinery's distillation units on 7 May 2008.
It continued: "At the time of the incident the line was not in use pending restart of a distillation unit within the Grangemouth refinery.
"The leak was quickly identified and isolated with temporary barriers put in place to contain the small amount of oil.
"This ensured that the leak was quickly cleaned up, minimising any risk to the local environment and to anyone working nearby."
Ineos also said the circumstances leading to the leak were subject to a full and thorough internal investigation and both the Scottish Environment Protection Agency (Sepa) and the Health and Safety Executive were kept fully informed.
It added: "A number of recommendations to prevent reoccurrence were identified by Ineos and these were acted upon."
Three days after that incident, a small fire was extinguished by firefighters at the Grangemouth refinery after oil spilled onto piping at the plant.
The fire broke out in a part of the site called the HydroCracker Unit.