An engineer called in to investigate a gas leak in an office block was nearly killed by carbon monoxide poisoning following faulty work on a boiler.

Cardiff Magistrates' Court heard John Courtney, 55, from Penarth, was almost overcome by deadly fumes when he was sent to investigate a possible gas leak at Mount Stewart House in Mount Stewart Square, Cardiff on 22 October 2010.

During the Health and Safety Executive (HSE) prosecution, the court heard Christopher Bates and Lewis John Rees, partners at BR Greenwell Heating and Plumbing Services of Llantrisant attended Mount Stewart House on 21 October 2010 to repair an open flue gas boiler. The men fitted a new gas control valve and left the premises.

The following day, Mr Courtney, an employee of Wales and West Utilities, attended the site following a report of a gas smell. When he entered the cellar to investigate, he suffered the effects of carbon monoxide poisoning and was taken to hospital.


When the fire service measured CO levels, they found there was more than 16 times the maximum safe CO level over an eight-hour period.

HSE's investigation found the gas valve was incorrectly adjusted so the boiler produced high levels of carbon monoxide.

Both defendants were registered with the Gas Safe Register but did not have an appropriate certificate under the Accredited Certification Scheme to confirm competency for work on the gas boiler, which was a commercial gas-fired hot water boiler.

HSE Inspector, Hugh Emment, said after the hearing: "Mr Courtney was an experienced engineer and had knowledge of the risks from carbon monoxide and training in gas work, but he was still affected by carbon monoxide.

"If one of the building's office workers had unknowingly entered the cellar with no knowledge of gas issues, they could have been quickly overcome by potentially fatal CO fumes.

"It is vital that gas engineers comply with the standards set down by law to prevent deaths from carbon monoxide. Since 2006 there have been three fatalities in the area because of registered gas installers working outside their confirmed competence."

BR Greenwell Heating and Plumbing Services of Castle Hill, Llantrisant pleaded guilty to a breach of Regulation 3 (1) and Regulation 26 (9) of the Gas Safety (Installation and Use) Regulations 1998. They were fined £5,000 in total and ordered to pay costs of £8,000.

(CD)