Vacuum cleaner caused £10m Cutty Sark fire as guard slept

The £10 million blaze was sparked by an industrial vacuum cleaner which had been left on for two days, an official report concluded.

Police and fire investigators found the Italian-made machinery had become blocked and probably caught fire after it had been accidentally left switched on during the weekend before the blaze erupted.

However, the investigation into what caused the fire revealed sloppy management of the renovation project and security guards who failed to do their job properly.

More than 40 firefighters fought the blaze which began shortly before 5am on 21 May last year at the ship's dry dock in Greenwich.

The three-masted clipper, which set speed sailing records for the voyage from Sydney to Britain in the 19th century, had been closed to the public while a £25 million renovation project was carriedout. Detective Chief Inspector Dave Garwood, who led the inquiry, said two security guards responsible for patrolling the site at night failed to spot the fire immediately.

He said the two guards were "vague and inconsistent" witnesses who made a "clumsy" attempt to hide a false logbook-entry. On the morning of the fire the guards had falsified a logbook which showed they had completed all routine patrols with no incidents reported. The final entry at 7am on 21 May read: "Booked off duty. All is in order."

The page had later been torn out of the book and was found in a waste bin.

In fact, the guards had failed to carry out regular patrols on the night and one had "dozed off " in the closed cafeteria while reading a bible.

Mr Garwood, a Scotland Yard homicide detective, said the guards - who were later sacked - may not have been able to stop the fire but could have reported it more quickly.

He said: "It is not unfair to conclude that the fire could have been detected earlier had they patrolled properly.

"It makes you wonder that if they had not taken the easy option and put their feet up then they could have prevented the effects of the fire taking hold."

The industrial vacuum cleaner which investigators believe sparked the blaze was being used to remove waste from the ship. Workmen said that no one had checked to see if it had been switched off after work had finished on the Friday before the weekend.

Tests carried out by fire investigators revealed that the Planet 200 cleaner, made by Soteco, caught fire if the filter became blocked and it was left on.

Mr Garwood said electrical equipment was often left plugged in, debris was not removed immediately and there were loose electrical connections.

Richard Doughty, chief executive of The Cutty Sark Trust, refused to comment on the claims of "lax management" of the site.

However, he said the trust was speaking to its lawyers about possible legal action involving the construction management company responsible for the site. He added that the blaze brought the total conservation bill to £35 million and set work back by at least two years.