The paramedics from St John ambulance train for major casualty events like aircraft and bus crashes, but nothing could have prepared them for the Christchurch earthquake.
A year on, senior officers still question their decisions: the what ifs, the life and death decisions made on an extraordinary day under extraordinary pressure, when everyone was doing the best they could in impossible circumstances.
Today as we remember those who died, we also remember those who lived thanks to the effort of doctors, nurses, rescuers and the St John ambulance.
In the first 24 hours after the quake St John ambulance received more than a thousand calls for help. They coordinated the triage and transport of dozens of critically injured patients.
Within hours Christchurch Hospital had reached capacity and St John coordinated a medical airlift involving 14 helicopters and six fixed wing aircraft.
On that day - like everyone - they gave it their all.
Watch the video for the full report