Auckland ambulance staff have defaced their own vehicles in protest at their working conditions.
Around 1000 St John staff went on strike in November, saying they wanted a pay rate that recognised their unsociable hours and the physical toll of their jobs.
With no progress in the pay talks, ambulance staff have taken to scrawling messages on their ambulances to drum up public support.
One St John paramedic, who wanted to remain anonymous out of fear of retaliation from his employer, said nearly every ambulance driven by a First Union member had been defaced. They were using liquid chalk so the vehicles were not permanently marked.
"It's up to each individual officer what to write, but they all know not to write anything derogative," he said.
"We are trying to get the public to ask us questions or come and approach us, and how we haven't been listened to.
"And also trying to make them aware of lot of things, a lot of them [public] don't realise that a good majority of us are degree qualified."
St John director of people and capability Sue Steen said the protesting staff were not being sanctioned - as long as the slogans were limited to the dispute, inoffensive and written in non-damaging materials.
"We respect our people's right to take industrial action while working in a safe and professional manner," she said.
Steen said they were committed reaching a resolution in the negotiations.
"We want our people's pay to match their skills and the workforce review findings will support our wider funding bid to Government later this year," she said.
The paramedic, however, was concerned they were being ignored.
"Everyone is quite disappointed, management had said they were going to work with us, but it really hasn't happened," said paramedic.
The union has previously said that staff were too often being offered up to cover sporting and other commercial events - instead of emergencies which was what the majority of Government funding was for.