A gas engineer praised for his "inspirational leadership" in the first report into the Grenfell Tower fire said he was not an unsung hero.
Jason Allday, who worked for Cadent Gas, was found to have risked his life alongside fire officers to cut gas supplies fuelling the tower block fire.
He led a check into the burning block as well as the team which eventually cut off its exterior gas supplies.
Some 72 people died in the west London fire on 14 June 2017.
"This report is for those who were affected by the tragedy at Grenfell Tower. I was just doing my job," Mr Allday said.
But Sir Martin Moore-Bick's report, published on Wednesday, goes into detail about the engineer's efforts.
It found Mr Allday turned up unprompted, took charge, and stayed for 24 hours.
Under his supervision, three substantial pipes under nearby streets supplying gas to the whole area were cut and capped in hazardous circumstances.
At some time between 14:00 and 15:00 BST "Jason Allday became aware that the London Fire Brigade was concerned about gas burning inside the tower when orange flames, which appeared to be fed by gas, could be seen in some compartments", the report said.
Mr Allday and fellow engineer Patrick Kelly went into the basement with firefighters using riot shields to protect them from falling debris to try to shut off gas valves but conditions inside prevented them from doing so, the report said.
His team from Cadent instead decided to cut gas mains in three streets adjacent to the tower.
The dangers included working inside the inner exclusion safety cordon around the tower, while a lack of proper equipment meant engineers had to adopt an improvised method to inflate airbags in the pipes to restrict the flow of gas before they were cut and capped, the report found.
When the gas was cut off at 23:40 on 14 June, Mr Allday described seeing the flames in the tower die down almost immediately.
Cadent team's success "was to a large extent due to Jason Allday's inspirational leadership, clarity of planning and careful execution", the report added.