Solihull-based pub chain Enterprise Inns has been fined £300,000 following the death of a pub landlord from carbon monoxide poisoning.
Paul Lee was found unconscious by a cleaner at the Aintree Hotel in Bootle, Merseyside, in November 2007, hours after he had turned on a gas fire in his living room before falling asleep.
The 41-year-old suffered a heart attack due to lack of oxygen on the way to the hospital and died the following morning without regaining consciousness. He had worked as the tenant landlord at the pub, owned by Enterprise Inns, for less than a month.
The company was prosecuted after a Health and Safety Executive (HSE) investigation found that the fire may not have been serviced since 1979 and the chimney was completely blocked.
The company, which owns around 7,700 pubs across the UK, admitted breaching Section 3(1) of the Health and Safety at Work Act 1974. The fine was imposed at Liverpool Crown Court.
Iain Evans, the investigating inspector at HSE, said: "It is shocking that a major pub chain failed to ensure regular gas safety checks were carried out at more than 400 of its properties. As a result, one man has been killed and hundreds of other lives have been put at risk.
"Tests we carried out on the gas fire at the Aintree Hotel showed that the workplace limit for exposure to carbon monoxide would have been exceeded within five minutes of it being turned on, and would have reached a level known to be fatal within an hour.
"The chimney from the fire was completely blocked so there was nowhere for the carbon monoxide to escape. Instead, it gradually built up in the room and starved Mr Lee's organs of oxygen until he was left unconscious.
"What makes this case so tragic is that Mr Lee's life could have been saved if Enterprise Inns had continued to obey the written warning it received about gas safety six years earlier, instead of falling back into old habits."
Sharon Lee, Mr Lee's sister, said: "Since Paul's death nearly three years ago, there is still anger and disbelief amongst his family and friends that it was entirely preventable.
"Paul's death will very possibly save the lives of others in the future, but it should not have taken the loss of his life to highlight the wider failings of Enterprise Inns."