It's dangerous work but Urban Search and Rescue squad leader Mike Carter prefers to focus on the task at hand, not the risky positions he and his colleagues are putting themselves in.
Their task is to enter highly restricted and prohibited areas - putting their lives on the line in order to save others.
Mr Carter is in one of three New Zealand Urban Search and Rescue (Usar) teams that have congregated with other emergency service workers to try to save those still trapped under tonnes of concrete, rubble and debris.
Taking turns, the teams spend hours planning, stabilising, then cutting their way into fallen and mangled buildings. It is hard, dirty and tiring work, but work that must be done in order to save lives.
Mr Carter's team arrived in Christchurch late on Tuesday night from Auckland and got straight to work, going right through the night and into yesterday. It was late in the afternoon before many of them slept.
So far the teams have had successes. Yesterday, the Auckland taskforce helped to pull two women and one man from the Pyne Gould Corporation building.
"It's a good feeling to see someone coming out, but it's a great feeling to see all three," Mr Carter said.
The job had its dangers, he said, and it was scary being trapped inside a collapsed building when the aftershocks struck. But he preferred to focus on the potential rewards, rather than the risks of what they were doing.
The work also involves working alongside the dead. In one case the legs of a man hung next to a tunnel one team used to get through the rubble. They couldn't help him, but Mr Carter said they did dig their way to a trapped and injured woman.
The rescue, like all of them, took time as team members had to stabilise the debris as they went.
At one stage they lost contact with the woman for nearly five hours. Unsure if she was still alive, they continued anyway and were eventually rewarded when they found her.
"She was underneath the desk and tangled up in the debris."
The woman had bad cuts to her hands and possibly a couple of broken ribs.
One man found early yesterday had to have his legs amputated so he could be got out. Another was rescued to the delight of his anxious wife and daughter, who stood nearby.
Similar Usar teams have arrived from several other countries, including Australia, America and Asia, to help the three New Zealand teams.
Taskforce 3 Usar planning and logistics manager Mike McEnaney said there were about 55 team members from Auckland, along with 12 additional staff who had brought additional resources and appliances down.
He admitted many were tired late yesterday after being up for two days straight but they were managing well.
Mr McEnaney said there was "every likelihood" other people remained trapped alive in some of the fallen buildings and people should not give up hope.
"We certainly wouldn't want anyone to give up hope yet at such an early phase."
The teams will remain in the city's centre for as long as it takes to search all the fallen buildings where people are trapped.