The claim appears to contradict earlier statements from DJs Michael Christian and Mel Greig that they were not aware of the approval process for prank calls.

The source says all presenters, producers and content managers are compelled to undergo "decency and standards" training every six months, in compliance with a ruling from the industry watchdog.

The training sessions, run by 2Day FM's in-house lawyer Tania Petsinis, include the specific instruction "not to air prank calls unless they get the subject's permission ... if there is doubt about a prank call, there is a clear chain of command in management that we have to escalate the call through".

The training sessions also advised on "how to not cause distress to callers ... there is a lot of stuff about taste and decency."

The sessions were introduced after the lie detector scandal of 2009, in which a 14-year-old girl revealed on air that she had been raped. The Australian Communications and Media Authority found the station had breached standards of decency and ordered it to implement a staff training program.

It is understood around 150 staff from 2Day FM attend the programs every six months – including Michael Christian and Mel Greig, the DJs who tricked Saldanha into thinking they were Prince Charles and the Queen.

If employees are hired between the twice-yearly sessions, they must have one-on-one training before they start.

"Even when we get people to do summer fill-in shows, they're not allowed on air until they've done the course," the source says. "And that training is very clear: you can't put any prank calls to air unless you get the subject's consent. It doesn't matter where [the subject] is from; this is a blanket rule.

"There's no way that Michael and Mel would have been allowed behind a microphone if they had not done this training."

Rhys Holleran, CEO of 2Day FM owner Southern Cross Austereo, told 3AW's Neil Mitchell the station tried "at least five times" to contact the hospital at which Saldanha worked before airing the prank call. He has not explained why his employees then broadcast the call despite failing to get consent.

The hospital has denied being contacted by 2Day FM and the station has not released phone records to prove the calls were made.

It is understood the 2Day FM training sessions make no specific mention of how to deal with prank call subjects who are overseas. However, attendees are instructed to "escalate" potential issues to senior staff.

"We're told that if we have any concerns about taste or decency, we have to take it up through the levels of management," the source said. "First, we have to take it to the content director, Derek Bargwanna, then to the legal team and the station manager, Jeremy Simpson."

Another source has told Fairfax Media that Bargwanna, a former producer of Kyle Sandilands and Jackie O, approved the broadcast of the prank call.

It is unclear whether Simpson, national content director Craig Bruce or metropolitan radio chief Guy Dobson also approved the segment.

Fairfax Media has repeatedly sought comment from Southern Cross Austereo spokeswoman Sandy Kaye and several senior managers. All have failed to respond.

On Wednesday Petsinis refused to confirm she conducts the "decency and standards" training for 2Day FM employees, and whether she gave legal approval to air the prank call.

The claims about the training sessions – particularly the advice not to air prank calls without the subject's consent – appear to conflict with Christian's claim on A Current Affair that "[we were] not privy to what happens with this call ... I'm certainly not aware of what filters it needs to pass through. All we know is that it's passed on and then we're told either yay or nay."

Greig added, "It's not up to us to make that decision. We just record it and then it goes to the other departments to work it out. I don't know what they then do with it. We just do what we do which is make those calls."

The source said, "I find it hard to believe that if you scored the scoop of the year in entertainment radio, you'd be so flippant as to not be aware of the approval process. You'd be asking questions every step of the way because you'd be trying to get it approved as quickly as possible. You're hardly going to sit back and wait.

"These two presenters are broadcast professionals. They can't play dumb now."

The source added, "I do feel sorry for them, though. I think they're taking the fall for the whole thing. There are senior people above them who would have approved this and so far, none of them have admitted their involvement."

In the wake of the scandal, Austereo suspended Christian and Greig and axed their national night program, Hot 30 Countdown.

It has since emerged that Hot 30 producer Emily Mills and assistant producer Ben Harlum were involved in producing and airing the prank call.

Both are reported to have "yapped like corgis" while the call was being made.

Harlum hung up when contacted by Fairfax Media. Comment is also being sought from Mills.

The scandal is the latest in a long line of controversies for 2Day FM, most of which involve breakfast hosts Kyle Sandilands and Jackie O.

Last year, Sandilands branded a female journalist who criticised his failed TV program a "fat slag" and threatened to "hunt her down".

The duo are also responsible for a stunt in which a handful of women were lined up behind two panels, exposing only their vaginas. A man was then asked to identify which vagina belonged to his girlfriend.

Another stunt involved flying in a woman from the United States, then forcing her to beg on her knees to see the aunt she had never met.

Last year, they were scolded by police for a win-a-car competition that may have encouraged dangerous driving.

Sandilands has also been criticised for making fun of a disabled baby and suggesting actor Magda Szubanski should be "put in a concentration camp" to lose weight.

2Day FM was also embroiled in controversy when former presenters Judith Lucy, Kaz Cooke and Peter Helliar revealed they were asked to host a stunt called "celebrity sperm". The station intended to ask singer Guy Sebastian for his sperm, then encourage female listeners to compete for the chance to impregnate themselves with it.

The trio refused to be part of the stunt.

mlallo@fairfaxmedia.com.au