The inquest jury at Wakefield Coroner’s Court had heard Joseph Johnson, 64, was installing aluminium lightning conductor tape at the side of Canon House on Dewsbury Road, Beeston, when the tragedy happened just after 12pm on Friday March 14, 2014.
The inquest jury recorded an open verdict after ruling that Mr Johnson had encountered “unknown difficulty” which led to his death.
Fire crews using an aerial ladder platform brought Mr Johnson down from where he was suspended at the side of the fourth storey of the building.
Mr Johnson, managing director of Johnson Technical Services Ltd, was taken to hospital where he was pronounced dead at 1.30pm that afternoon.
A post-mortem examination revealed Mr Johnson, of Inman Grove, Knaresborough, died of hypoxia after his body was deprived of sufficient oxygen due to neck compression from a strap or rope.
Mr Johnson was on his final abseil as he finished off installing lightning conductor tape.
At the inquest, Deputy Coroner Kevin McCloughlin asked Mark Hatfield of the Health and Safety Executive: “We have an experienced man who, when something has happened previously, knew to lower himself to the ground. In this case it seems as though something has happened that didn’t give Mr Johnson that option. Can you help us understand what that might be?”
Mr Hatfield replied: “No, I’m afraid I can’t. I would love to be able to give you the answer, but I can’t.”
Mr Johnson’s son Samuel had been working with his father at the building that morning but left for a doctor’s appointment before the tragedy happened.
Joseph and Samuel Johnson and another employee, Ashley Spence, had all previously completed abseils that morning.
Giving evidence, Mr Spence said was on the roof of the building when Mr Johnson began the final abseil.
Mr Spence said Mr Johnson was and was around two to three metres from the top of the building when he got into difficulty.
Mr Spence told the inquest he saw Mr Johnson struggling and had tried to pull him up.