Malcolm Williams, of A1 Auto Gas in Hereford, was fined £1,000 and ordered to pay £1,000 costs for faulty conversion work, which experts say could have caused a fire. A local garage spotted the unsafe conversion when the owner complained of an excessive petrol smell.
Environmental Health and Trading Standards officers had the vehicle examined by an expert who said there was a number of faults.
Williams pleaded guilty at Hereford Magistrates' Court to making vehicles unsafe by incorrectly fitting LPG conversion which he claimed complied with the safety requirements of the LP Gas Association code of practice.
The most serious fault was that the conversion did not have an electronic safety valve fitted as near as possible to the gas tank. If the supply line under the vehicle ruptured, the gas would leak uncontrollably, creating a risk of fire or explosion.
Suzanne Laughland, Herefordshire Council principal trading standards officer, said: 'This is a serious safety issue. 'A customer asking for conversion should ensure the trader has had suitable training and a good reputation to better guarantee their safety.'