More than 400 ambulance staff are attacked every year in Northern Ireland, new figures show.
The attacks ranged from verbal to physical, including biting, lacerations and bruising.
Frontline staff including paramedics, emergency medical technicians and attendants have been left with injuries which include concussion, sickness and pain.
The chief executive of the Northern Ireland Ambulance Service, Michael Bloomfield, said the level of attacks is of great concern to him, both in terms of the impact on staff and the implications for areas being left without cover.
There were 433 attacks in 2018, down slightly from 493 attacks in 2017 and 438 in 2016.
Most incidents took place in private residences and ambulances.
They resulted in a number of staff taking sick leave: 17 in 2018, 14 in 2017 and 19 in 2016.
The figures, obtained following a Freedom of Information request, also revealed there were 36 attacks on ambulance staff in January 2019 alone.
Last December, an area of Northern Ireland was left with significantly reduced ambulance cover on a Saturday night after two of the three crews on duty were attacked and unable to continue.
Three ambulance workers were hurt in separate assaults in the North Down area.
The ambulance service said at the time the level of ambulance cover in the area was "compromised for the second weekend in a row" as a result of "injuries sustained by staff responding to emergency calls".
Michael Mulholland of the GMB union, which represents ambulance service staff, condemned the attacks.
"I categorically condemn attacks on paramedics who are primarily there to save lives and administer first-line medical care to people," he said.
"Any attack on paramedics has to be completely refuted and the perpetrators must be caught and face the full extent of the law."
Mr Bloomfield said: "These attacks are of great concern to me personally. They occur too frequently and the immediate impact is twofold.
"Firstly, our front-line staff may receive physical injury which is totally unacceptable to them, us and society in general.
"Secondly, these attacks often result in our levels of cover being reduced, as staff are unable to continue with their duties.
"This will mean that areas may be left vulnerable as a result of longer response times as crews are dispatched from neighbouring stations.
"This could have potentially tragic consequences for those who may have need of our service.
"Once again, I appeal that our staff be allowed to do their job without interference of any sort and, for those who do not respect that appeal, I have no hesitation in calling for appropriate action to be taken against perpetrators through the judicial system.
"I am also concerned about the lasting emotional and psychological impact of these attacks on our staff.
"Physical wounds heal much quicker, but we know that the emotional trauma can sometimes remain with our staff for a number of years.
"They deserve better and we will continue to support them through measures available to us, including immediate management and peer support, which will continue for as long as necessary."