Coroner of Inquests Michael Moyle has recorded an open verdict into the death of a Liverpool diver two years ago.
Experienced diver Michael Bromsgrove drowned off Bradda Head in 2006 on what was described as a simple dive.
Last month Mr Moyle finished hearing evidence from experts about whether Mr Bromsgrove’s equipment had failed.
But he said there was insufficient evidence to suggest either design flaws or that Mr Bromsgrove had forgotten to switch on his rebreather unit.
In his conclusions, Mr Moyle said it was hard to believe the 41 year old could have forgotten to switch on his life support kit, although it had been switched off when his body was retrieved from the water.
He said equally there was no evidence that batteries had been shaken loose as Mr Bromsgrove had entered the water.
Mr Moyle said in the circumstances he could not say for certain what had happened on that day in 2006.
He recorded an open verdict and expressed his condolences to Mr Bromsgrove’s family.