"I'd see the ambulances coming and going and always wondered what they did before they got to the hospital," she said.
"I was only seeing the patients once they were stabilised and relieved so was very intrigued."
Observers ride along with paid staff or experienced volunteers to see first hand what the role entails.
"You learn about all the equipment, how to use the radio, and you get to watch how a job plays out and see if it's what you want to do," Jenyns said.
Jenyns, who volunteers on weekends, said the job was kept interesting by the varying aspects to the role.
"We do get a lot of trauma calls – those are the thrilling calls ... we also go to a lot of medical calls where people are struggling to breathe, heart issues, things like that.
"These are the more rewarding calls because you can see how you're really helping somebody."
Jenyns said that was especially important given how often they knew the patient.
"I think that it's nice to be able to provide comfort in their worst time."
People who felt deterred by a lack of medical expertise could gain the skills through the variety of training and courses available.
And anyone who didn't fancy a frontline role was also welcomed to help the Dargaville branch fundraise or build their profile within the community.
People interested in volunteering can contact the St John Dargaville Ambulance Station via Facebook, visit join.stjohn.org.nz, or call 0800 ST JOHN (0800 785 646).
They can also visit the Normanby St station during their training evening every second Tuesday between 5.30pm and 6.30pm.