It does not need to be a major trauma incident — in fact, it could be something as minor as a stubbed toe.

But that could be enough to make an emergency service worker spill over, if their "bucket" was full.

Lauren Hepher, with Tim Jacobson, said first responders use a bucket as a metaphor. ( ABC News: James Dunlevie )

The "bucket", as ambulance paramedic Lauren Hepher explained, was the shorthand by which she and her colleagues referred to the finite capacity of their coping mechanisms.

Ms Hepher told those in attendance at an inquiry looking into the high rates of "mental health conditions experienced by first responders, emergency service workers and volunteers" of how for most in the business of attending road crashes, domestic violence call-outs and other serious incidents, the bucket was near to overflowing most of the time.

Ms Hepher, who is also the president of the ambulance employees' Tasmanian sub branch of the Health and Community Services Union (HACSU), said attending an incident with a child of similar age to one's own, or an elderly person of similar age to a relative, was the kind of thing that could fill the bucket.

The Hobart hearing heard of the heavy toll that stress took on emergency service personnel, with everyone giving evidence mentioning they had knowledge of someone who had taken their life.

Scott Fyfe told the hearing by telephone that it might not be one particularly bad incident that might do it, instead saying that the "cumulative exposure" to scenes of human distress weighed heavily and admitting he had "seen too much".

Mr Fyfe, an intensive care paramedic, told the hearing by phone he too employs the metaphor of the bucket.

"I use that all the time," he said.

Robert Atkins and Lyndsay Suhr said more training for brigade leaders to identify stress in team members should be rolled out. ( ABC News: James Dunlevie )

Robert Atkins and Lyndsay Suhr, veteran firefighters representing Tasmania's volunteer brigades, told the hearing there needed to be more training for those with the job of identifying when stress was wearing down a team member — not easy, when that person may be doing everything they can to hide the symptoms.

Mr Atkins said for him and others in volunteer fire brigades around Tasmania's rural areas, the nerves started the moment the alert went off that there was a job in need of people.

"Is it someone I know?" he said was the first thought that came to mind.

Both agreed more should be done to train up brigade senior staff to better recognise the signs of stress in the team members.

Mr Atkins said team leaders knew among their crews some people could be relied on to do certain things well, but were best quarantined from other tasks once on the scene.

"We know that person, when it comes to MVA (motor vehicle accidents), they are very good at driving vehicles, but that's where they stop," he said.

When volunteer brigades attended incidents in rural areas, it was a case of "don't know until you get there", Mr Suhr said.

Sometimes, "you just have to keep people away" from the worst of it, he told the hearing.

Peter James, a decorated paramedic of 42 years service, was scathing of how PTSD is dealt with. ( Supplied: Government House )

'A very unsupportive workplace'

Peter James, a veteran of 42 years in the Tasmanian Ambulance service, wrote in a submission to the hearing he had first been diagnosed with PTSD in 1997 after attending the Port Arthur Massacre the year before.

"Soon after returning to work after Port Arthur, I was told by a supervisor that any stress I experienced was my own fault. Sadly for the next 20 years I received no support."

Despite that, Mr James wrote he had continued working and performing "all regular duties on road and in the air of an intensive care paramedic", attending at the Beaconsfield mine rescue in 2006 and at the 2011 Christchurch earthquake, where he was "searching for victims and body parts".

He said at Beaconsfield there was "no post-incident psychological debriefing", and after Christchurch he was told that despite working a "kilometre underground, in a seismologically unstable mine, with blasting", such conditions were not regarded as a "significant event".

Mr James said the workers' compensation process in dealing with people seeking help for PTSD was "adversarial in nature".

"You are a liar until proven otherwise, and if the claim is accepted, you are a liar that got away with it."

He said the workplace culture and management practices were "generally toxic" within Ambulance Tasmania.

"It operates on negative management; you only interact with management when there is a problem. It is a very unsupportive workplace.

"Ambulance Tasmania management is reactive, not proactive, and are not transparent in their approach to workers, nor are they consistent with how individuals or issues are managed."

He said he believed there was "little empathy practiced by Ambulance Tasmania managers" in regards to issues of mental health, "largely due to the lack of training in the area".

Despite what he had gone through in his 42 years as a paramedic, Mr James said would not want to work in any other field.

"Paramedics at times see things that no human should see, yet I would do it all again tomorrow."

In a statement released today, Minister for Health and Minister for Police, Fire and Emergency Management Michael Ferguson said the Government "know first responders are exposed to stressful situations, which is why we are putting more resources into mental health and wellbeing services for our emergency service workers".

The Senate committee will reconvene in Adelaide and Fremantle in August.