A labourer left paralysed and brain damaged after plunging down a storm tank was in no way to blame for the accident, the High Court has ruled.
Lester Cowan was not properly warned about the risks surrounding dangerous and defective decking with totally inadequate covering, a judge said.
The 57-year-old has no memory of the incident at a pumping station in Bangor, Co Down.
But Mr Justice Gillen rejected claims he was guilty of any contributory negligence.
A further hearing will now determine the level of damages to be awarded.
Mr Cowan, from Lisburn, employed by another sub-contractor, sued over the accident in June 2009 during work by contractors on the Northern Ireland Water-owned site. His case against J Graham Dromore Ltd alleged negligence and breach of statutory duty.
Although no-one witnessed him fall, the court heard he was found at the bottom of the tank where foul pumps were located.
Roof decking had been completed, with plywood sheeting used to cover holes until proper lids were fitted.
Mr Justice Gillen held that he fell into the tank due to the defendant’s negligence in failing to adequately cover the holes and provide an adequate means of access.
“For no good reason other than a desire to complete the job, the task of providing proper metal lids on the storm tank was neglected even though these were due to arrive a number of days hence,” Mr Justice Gillen said.
The judge confirmed: “The overwhelming danger created by the breach of statutory duty and negligence of the defendant has created a danger causing the plaintiff to fall and sustain his catastrophic injuries.”