An Urban Search and Rescue (Usar) member who took part in the "chaotic" rescue efforts at the collapsed Canterbury Television building says a senior Fire Service representative should have been in charge of the site.

Sockburn senior station officer and Usar member David Berry has given evidence on the fifth day of a coroner's inquest in Christchurch today.

The inquest is hearing evidence into the deaths of Tamara Cvetanova, Jessie Redouble, Emmabelle Anoba, Ezra Medalle, Reah Sumalpong, Rika Hyuga, Chang Lai and Mary Amantillo, who were known to have been alive after the building collapsed in the February 2011 earthquake but were unable to be rescued.

Berry said he arrived near the CTV site about 3.15pm on February 22 last year after seeing smoke coming from the building during a helicopter ride into the city centre.

He undertook a "360 inspection" of the site to assess the situation and see what work was going on.

"I remember seeing so many people, it didn't look as though anyone was in charge and things were rather chaotic."

Berry said there were two lines of people "working like human chains" to remove debris and pass along rescue tools.

"It wasn't very effective and things were going in all directions."

After helping to organise the group, he handled the western side of the building, while another Usar member co-ordinated work on the eastern side.

The pair communicated using a runner as Berry did not have any radio equipment with him, which made co-ordination difficult.

"I like to talk to a person and get a feeling of what's happening one on one. It worked, but it just wasn't effective as talking one on one," he said.

Rescue workers on the western side created a metre-high tunnel to rescue survivors and remove victims from the building.

Berry said firefighters were cutting their heads on the narrow tunnel as they went in, and the conditions were difficult to work in.

"It was hot, sweaty, smelly. There was a lot of smoke and there was also the smell of burning corpses. It was pretty ugly."

He said the workers managed to save eight people and pulled bodies from the site.

Berry said health and safety concerns "didn't exist at that stage", with the rescuers continuing to work through aftershocks.

"It was a free-for-all, basically. Guys were being held by their ankles, and if an aftershock occurred he'd just be pulled out by his ankles."

He left the site about 4am the next day to go home.

Berry said he did not view himself as the person in charge of the site, and a Fire Service executive officer should have taken control of the rescue operation at the building.

"At no time did I consider I was in charge of the whole site ... There should have been someone above me communicating via a runner."

A senior officer could have been in charge of keeping track of how many people were working at the site, assigning tasks to different teams and providing an overall perspective for decision-making.

"That's really important because a decision made on one side of the site to help could have a negative impact on the other side," Berry said.

He said a safety officer should have been appointed earlier, with officers for each side and another one in charge of the overall rescue effort.

The inquest, which is being streamed live on the Justice Ministry's coronial services unit website, will run for two weeks and reconvene for a final week at the start of December.

- © Fairfax NZ News