Blind diver Mark Threadgold plans to complete a 100m dive using a trimix closed-circuit rebreather, the deepest dive ever attempted by a blind person. The 38-year-old from Brighton, who is the first blind diver to use a closed-circuit rebreather, will attempt the world record in June next year at the Blue Hole dive site in Dahab, Egypt.

'It's sticking two fingers up at those people who say disabled people can't do things like this,' Threadgold told DIVE. 'There's a huge amount of discrimination against disabled people, and an staggering amount against blind people in particular.'

Threadgold, a former sergeant in the Royal Corps of Signals, lost his sight completely after suffering horrific head injuries in an accident in 1999. He learned to dive five years before he lost his sight and was determined to carry on with the sport as a blind diver. After learning new techniques to cope with a loss of sight underwater, Threadgold decided to become an AP Valves Inspiration closed-circuit rebreather and trimix diver in February this year.

'The hardest thing was getting used to buoyancy and sorting out hand signals, not only for the diving but also for the different skills I had to do in the water,' he said. 'AP Valves changed the alarms on the rebreather, so there is a different sound for each warning, such as high O2 or low O2 readings.'

It was after completing this course that fellow rebreather divers suggested he go for the world-record attempt, which is being sponsored by holiday operator Neilson. This is not the first time that Threadgold has attempted a blind world record. He has set three boating world records, including the 73mph world speed powerboat record in Lake Windermere in 2003.

He hopes his latest record will raise the profile of St Dunstan's, a charity that helped him rebuild his life after his lost his sight. The charity helps rehabilitate blind ex-servicemen and women.

Three support divers will accompany him on the 100m dive. He said he is feeling slightly apprehensive, but is looking forward to his latest challenge. I probably am a bit crazy for doing this,' said Threadgold, 'but I'm confident in the team and support I have.'