A company was found guilty today of a health and safety breach in connection with the huge explosion at the Buncefield oil depot.
Motherwell Control Systems 2003 Ltd, which is in voluntary liquidation, was convicted of the offence at St Albans Crown Court, the Health and Safety Executive (HSE) said.
Jurors returned a guilty verdict to a charge that the company failed to ensure its employees were not exposed to health and safety risks between September 28 2003 and December 12 2005, an HSE spokeswoman said.
The destruction at the Hertfordshire depot came after a massive vapour cloud ignited when 250,000 litres of petrol leaked from one of its tanks.
Widely thought to be the largest explosion in peacetime Europe, the blast measured 2.4 on the Richter scale and could be heard 125 miles away.
Total UK has already admitted three health and safety breaches in connection with the explosion, while the British Pipeline Agency Ltd has also pleaded guilty to two charges.
The case is being prosecuted by the Health and Safety Executive and the Environment Agency.
The trial opened on April 15 and the jury retired on June 10.
The court heard that the explosion at the depot, near Hemel Hempstead, on December 11 2005 was similar to an earthquake.
The environmental damage caused was still not known but could last for decades, jurors were told.
Jurors are considering their verdict against TAV Engineering Ltd, of Guildford, Surrey.
The company denies committing a health and safety breach between October 1 2003 and December 12 2005.
The jury of 11 men and one woman will resume its deliberations tomorrow.