The Health and Safety Executive (HSE) has warned of the need for effective operation, inspection and maintenance regimes to ensure the safe use of pressure equipment, following the prosecution of a chemical manufacturer.

The warning comes after Giancarlo Coletti, 48, a worker at Clariant Life Science Molecules (UK) Limited’s plant in Sandycroft, Flintshire, sustained serious injuries to his right arm in October 2003. The accident happened when the clamping system on a pressure vessel lid he was operating failed, causing the lid to fly off and hit him.

Clariant Life Science Molecules (UK) Limited was fined £100,000, split equally between Regulations 11 and 12 of the Pressure Systems Safety Regulations, with £24,474 costs, at Mold Crown Court on 17 December 2004 after pleading guilty at an earlier hearing. The company admitted failing to provide workers operating the pressure vessel with adequate and suitable instructions for its safe operation and also failing to ensure the vessel was adequately maintained.

HSE Inspector, Dr Stuart Robinson, who investigated the incident, said: “Our investigation revealed serious deficiencies in Clariant’s safe systems of work. Opening and closing of the lid was regarded as a simple process, carried out three times a day, but the hazards had been overlooked. Although the clamping system was designed with a substantial margin of safety, it had been allowed to deteriorate to such an extent that the risk of injury became unacceptably high.”

In particular, HSE’s investigation found that Clariant had failed to put in place adequate operating procedures to ensure the system was used correctly. For example, clamps were regularly over-tightened, occasionally causing them to break and the system was allowed to operate with less than its full complement of eight clamps.

At the time of the accident, one of the clamps was missing and others showed excessive wear and tear, or inadequate repair. Furthermore, it had become common practice for leaks to be nipped up with the system under pressure because the operating procedures failed to state that the system should be depressurised first.

Robinson added: “The investigation also revealed that although Clariant had arranged for an independent competent person to examine the pressure system periodically, this was insufficient due to the frequent operation of the clamps, and the high level of wear and tear they showed. Instead, the firm should have introduced a more frequent system of inspection and maintenance.”