- Associated Press - Thursday, November 10, 2011

CHRISTCHURCH, NEW ZEALAND Passing trucks shook the six-story office building constantly in the months after a 7.0-magnitude earthquake in September 2010.

“There were quite big cracks. You could see daylight from some offices with outside walls,” said receptionist Maryanne Jackson. But, she added, “there was a green sticker on the door that said it was fine.”

It wasn’t.

The Canterbury Television building collapsed into a smoldering heap when a second major quake struck the New Zealand city of Christchurch five months later. The 115 who died in that building alone accounted for nearly two-thirds of the 181 victims.

The Feb. 22 tragedy has exposed shortcomings in a rapid-assessment system that was pioneered in California and is used around the world to determine whether buildings can be reoccupied after major earthquakes.

Inspection reports obtained by the Associated Press under New Zealand public records laws show just how cursory the checks can be.

They don’t take into account what predictably follows any major earthquake; namely, aftershocks. Christchurch was hit repeatedly, as was northern Japan after its devastating earthquake and tsunami in March.

The problem is that people place more faith in the inspections than they should. A green sticker is no indication a building will withstand future quakes, nor does it require a robust analysis of a building’s structural health - something that was misunderstood by building occupants and public officials in Christchurch.

The experience may serve as a wake-up call for cities from Tokyo to Athens that rely on the system. California officials have told the AP they plan to make improvements after reviewing what happened in Christchurch, and those changes will likely set the tone for the rest of the world.

The rapid-assessment placard system was developed in the 1970s and first used after the 1989 Loma Prieta earthquake in the San Francisco Bay Area. Officials quickly inspect buildings and assign a red, yellow or green tag to indicate whether people are banned from the building, can gain restricted access or are able to go back to work.

The father of the system, Oakland-based structural engineer Ron Gallagher, said it’s often about triage, and officials sometimes make judgment calls based on instinct while trying to juggle assessments of hundreds of buildings.

The responsibility for a full inspection, he added, lies with building owners.

On a visit to Christchurch after the February quake, Mr. Gallagher found problems.

“We heard from a number of people that when the public viewed a green tag, they thought it meant the building was safe from future earthquakes,” he said. “That’s not the way the placard system is used, or is meant to be used.”

Green stickers were issued to two buildings - Canterbury Television and Pyne Gould Corp. - after the September quake based on limited examinations, according to the inspection reports obtained by the AP.

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