Illness has forced an inquiry into the Canterbury Television building collapse to be adjourned.
The Canterbury earthquakes royal commission was today abandoned for the week because commissioner Ron Carter was unwell.
A commission spokeswoman said Carter's illness was not serious.
It was hoped the eight-week schedule would be maintained when the hearing resumed Monday.
'Poor evidence' flaws report
The CTV building wreckage should have been treated like a crime scene to prevent the "wholesale destruction" of evidence, a consulting engineer says.
International expert Robin Shepherd was commissioned by the lawyer for Alan Reay Consultants, the building designer, to review a Department of Building and Housing (DBH) report, including the evidence used in the report.
He told a royal commission hearing yesterday poor evidence collection resulted in a flawed report.
Traffic fatalities in New Zealand were treated as police-controlled crime scenes, but no procedures for building collapse existed.
"Rescue and recovery activities must clearly have priority, but need not be followed by the wholesale destruction of evidence as appears to have occurred in the CTV site and dumping of the debris in the Burwood landfill," Shepherd said.
"If competent observers had the opportunity to identify and record elements of interest as the site was cleared, and if a rigorous chain of custody record had been instigated and maintained, it is very probable that many of the questions before this commission could have been answered with greater confidence."
The commission heard in the first week that urban search and rescue (USAR) engineers Rob Heywood, Graham Frost and John Trowsdale saved material at the site in the hours after the quake for use in an inquiry.
Shepherd was impressed with their efforts, but said none had been commissioned to carry out a forensic assessment.
Almost no attempt had been made to identify structural elements before they were dumped, he said.
When questioned by counsel for the commission, Mark Zarifeh, Shepherd said his views on the recovery effort were based largely on overseas media reports.
Zarifeh asked if it was "normal" for an expert witness to use newspaper reports to "base their understanding of facts".
Newspapers were "one source", Shepherd said.
He had not visited the landfill where the debris was stored, had not seen photographs of the site, and could not recall having seen all the evidence presented by the USAR engineers.