The manager of the Canterbury Television building which collapsed in the devastating Christchurch earthquake, killing 115 people, says he will forever question what might have been done differently.
Yet up until the 6.3-magnitude quake on 22 February last year, John Drew says he still had complete faith in the building's structural integrity.
The Canterbury Earthquakes Royal Commission is investigating why the building collapsed.
Mr Drew told the hearing on Monday that in 2010, the CTV building was given green stickers after a 7.1-magnitude quake on 4 September and a 4.9-magnitude quake on 26 December, meaning it was safe to enter.
He said he was confident that the building was structurally sound and complied with the building code.
"I never for a minute had any thought that the building might be at risk of collapse. Since February 22nd, I have felt a huge sense of responsibility and I am forever questioning what might have been done differently."
Mr Drew said an independent engineer's report after the September quake also ''indicated the tenants were OK to stay''.
The Royal Commission was told on Monday that a recommended inspection of a major structural wall was not carried out.
The shear wall was covered with CTV's electronic equipment at the time. John Drew said the inspection was not done because he understood this would shut the TV station down and a further inspection was not conveyed to him as something major that needed to be done urgently.
Brian Kennedy, whose wife Faye died in the building, said he did not accept the condolences offered to victims' families by Mr Drew on Monday.
Mr Kennedy said the day's evidence sparked a range of emotions including frustration, anger and disappointment.