Kim Jenkins knows the man in the security camera footage is her dad, but his behaviour is far from recognisable.

In the video, Tony, a New South Wales ambulance officer, is buying equipment at a hardware store in Newcastle.

The 54-year-old appears calm and methodical, even though he is planning to use that equipment to kill himself.

"He walked up to the counter, didn't look at the girl at all, took what he needed, and left," Ms Jenkins said.

Tony Jenkins with his daughters — his family says there was no reason to suspect that he was suicidal. ( Supplied )

According to his family, there was no reason to suspect Mr Jenkins was suicidal.

He had been a paramedic for almost three decades and he loved his job.

"He took great pride in making people feel safe and he made us feel safe.

"That's just the sort of person he was," his wife Sharon Jenkins told Background Briefing and 7.30.

Mrs Jenkins said there was nothing unusual about the 9th of April.

Her husband left for work in the morning and was not expected to return until 10:30pm.

But when he failed to show by 2:00am the following day, she picked up the phone.

"I made 17 calls and I didn't get any answer from any of those calls, I was starting to panic." she said.

Tony's wife, Sharon Jenkins, said at first she didn't believe NSW Ambulance representatives when they said her husband was dead. ( ABC News: Laura Brierley Newton )

About five hours later, she received a knock on the door.

Two representatives from NSW Ambulance, accompanied by police, confirmed her worst fears.

Her husband was dead, they told her.

"I didn't believe them," she said. "One of my daughters collapsed."

"No witnesses, no minutes, no recordings"

Sharon Jenkins would later discover her husband was called into a meeting at NSW Ambulance headquarters in Newcastle just hours before he took his life.

During the meeting, he was accused of stealing fentanyl, a painkiller so strong a dose the size of 10 grains of sand can kill someone.

They also claim Mr Jenkins admitted guilt when confronted with these allegations, although there are no contemporaneous notes taken at the time of the confession.

NSW Ambulance guidelines require prior notice before such meetings can take place and official minutes to be recorded.

Sharon Jenkins said that did not happen.

"There were no notes, not witnesses, no minutes, no recordings," she said.

"Why would you do it like that? Why wasn't it done correctly?"

Louie, Tony Jenkins' dog, sits on her bed. ( ABC News: Laura Brierley Newton )

Mrs Jenkins understands her husband told Ambulance NSW that he was feeling vulnerable.

He was, according to those in the meeting, relieved to have been caught as it gave him an opportunity to seek help.

But despite his fragile state of mind, Mr Jenkins was allowed to leave his ambulance station alone.

"I think I screamed at them," Mrs Jenkins said.

"I knew they had a chance to stop him and they could have."

Tony Jenkins was allowed to leave his station alone — "they had a chance to stop him," said Mrs Jenkins. ( ABC News: Laura Brierley Newton )

NSW Ambulance Chief Executive, Commissioner Dominic Morgan, questions this version of events.

He defended Ambulance NSW's handling of the situation.

"If our fact-finding shows anything to the contrary then I'll be the first person to take that to Sharon and the rest of the family and admit that we did fail in our duty of care," he said.

"But from what is in front of me at the moment, it would appear that they've dealt with it the best that they could."

Commissioner Morgan did say that Mr Jenkins spoke about having depression and difficulties sleeping but that he had visited his GP and planned to talk to his wife about it.

After the meeting, Mr Jenkins instead drove to the hardware store and then to bushland near a sailing club on Lake Macquarie.

His body was discovered early the following morning.

"It was as though a switch must have flicked in his mind between when he walked into that meeting and asked for help and when he walked out knowing he had no other choice," Mrs Jenkins said.

"It concerns me greatly that a person with that reputation could find themselves so desperate that their only option was to turn to drugs of addiction," Commissioner Morgan said of Tony Jenkins. ( Supplied )

Not the first, or the last

Paramedics in Australia have the second highest rate of suicide of any emergency services workers, including police, firefighters, and prison guards.

It is no secret many steal and misuse addictive drugs, including fentanyl, to treat conditions like post-traumatic stress disorder.

Background Briefing and 7.30 have obtained documents under Freedom of Information revealing the widespread practice not only poses a safety risk to first responders but the public, too.

In the last eight years there have been almost 100 investigations into cases involving paramedics misappropriating addictive drugs across the country.

An ambulance officer overdosed on fentanyl in Western Australia in late 2014 and died.

Two years later, in Queensland, a paramedic was found to have fraudulently altered official records in an attempt to conceal their theft of the drug.

The largest number of investigations, however, were in New South Wales.

There have been 36 incidents in that state, one of which involved a paramedic who overdosed on fentanyl twice in the same day.

The documents also detail how some ambulance officers caught stealing fentanyl attempted to refill the emptied ampoules with other substances, including saline and water.

Following Tony Jenkins' death, NSW Ambulance launched an investigation into the misuse of addictive drugs by staff in the Hunter region.

"He was this well-respected, well-regarded professional and it concerns me greatly that a person with that reputation could find themselves so desperate that their only option was to turn to drugs of addiction," Commissioner Morgan told Background Briefing and 7.30.

"Tony's family needs answers and I need answers and I will not stop until I get those answers."

Paramedics in Australia have the second highest rate of suicide of any emergency services workers. ( ABC News: Laura Brierley Newton )

NSW Ambulance has taken the extraordinary step of quarantining 40 vials of fentanyl from four ambulance stations and sending them off to laboratories to be tested for any sign of tampering.

Shayne Connell, a suicide prevention councillor who is also Mr Jenkins' nephew, spoke to NSW Ambulance representatives about the problem.

"This is not a matter of isolated staff members potentially doing the wrong thing," he said.

"We've been told this is a pattern — Tony was not the first. He won't be the last."

This should come as no surprise to NSW Ambulance.

The misappropriation of fentanyl was first exposed during a state parliamentary inquiry in 2008.

NSW Ambulance Commissioner Dominic Morgan says he takes full responsibility for the fact that fentanyl tampering still occurs.

"It's terribly inappropriate and concerning to me that [patients] were administered saline because that would have meant that they had in fact had inadequate pain relief," he said.

"There is absolutely no doubt that the robustness of those systems and processes are my responsibility."

Mr Jenkins' daughter, Kim, says she believes that NSW Ambulance needs to focus on the mental health of long-serving paramedics like her dad as a priority.

"They go into a job that is stressful and they have that long term trauma," Kim Jenkins said.

"They are not supported and they are around these very potent dangerous drugs — it's a complete recipe for disaster."