A coroner's found the delayed response when a man collapsed at a prison gym, probably lowered his chances of revival

38-year-old Henry Afakasi died of a heart attack at Auckland South Corrections facility in 2016.

Coroner Katharine Greig's found Corrections gave adequate cardiovascular care, and prisoners did their best by putting him in the recovery position.

But once they realised he wasn't breathing and began CPR, staff didn't call an ambulance for another two minutes.

She recommends clarifying when staff should call 111, and regular first aid and defibrillator training.