THE last thing David Iredale would have expected when he called triple-0 was sarcasm. But that's what the Sydney schoolboy received during frantic calls for help when he became lost while bushwalking in the Blue Mountains.

"OK, so you have just wandered into the middle of nowhere, is that what you're saying?" was one operator's response. "There's no need to yell," was another's.

The last photo of David Iredale, left, and Kostas Brooks, and the note they left at the top of Mount Solitary.

The officer in charge of the Redfern call centre of the NSW Ambulance Service yesterday admitted there were serious deficiencies in the way the 17-year-old was dealt with when he made five calls to the ambulance service about midday on December 11, 2006.

Superintendent Peter Payne told an inquest into David Iredale's death that uncaring, sarcastic and dismissive attitudes among phone operators had been a "disease" within the organisation.