Two fires that destroyed about 200 properties in the NSW Blue Mountains in 2013 were ignited after a tree and a branch hit power lines, a coroner has found.
The blazes at Springwood and Mount Victoria both began on October 17, 2013, and collectively burnt through more than 12,000 hectares of land over a period of nearly a month.
Handing down her findings at the Katoomba Coroner's Court on Wednesday, deputy state coroner Fiona Toose said the Springwood fire was sparked when a tree hit power lines operated by power company Endeavour Energy.
Power lines owned by the same company were also hit by a tree branch in Mount Victoria, sparking the fire there, the coroner said.
The fire rating was "severe" on the day, the magistrate noted, with the top temperature of 26C forecast to be paired with winds gusting up to 80km/h.
Evidence from the inquest made it obvious the tree that fell in Springwood had been "diseased" and likely to fall in strong winds due to its hollow core.
The tree that fell in Mount Victoria was also "defective".
Neither tree had been identified as an issue by Endeavour Energy contractors tasked with scoping areas near the company's poles and wires and reporting on dead, damaged or dangerous vegetation, Ms Toose said.
During the inquest it became apparent there were some "ambiguities" in the power company's policies around vegetation management, she also noted, including the definition of a "hazard tree".
Endeavour Energy's policies have since been amended.
But among the coroner's eight recommendations was for the company to clarify in "clear and concise wording" its expectations of contractors in that regard.
She also recommended Fire and Rescue NSW and the Rural Fire Service offer firefighters further training in dealing with blazes near electricity.
That came after videos from the scene of the Mount Victoria blaze demonstrated the danger of such situations.
Nobody died in either of the 2013 fires, but 194 properties were destroyed in the Springwood blaze and another 650 homes affected.
Nine properties were ruined in the Mount Victoria fire and another 61 affected.
