Despite being roped into posing for the calendar, Kahlia said she was glad she had joined the fire brigade, which she described as like a big family.
"It can be challenging at times - about a month ago I went to an accident where I knew the people. That was the first time for me, so that hit me a bit. But other than that it's good, and it's great to know you're helping people and their families," she said.
The calendars have been produced annually since 1990, originally to help firefighters compete overseas at events such as the World Firefighter Games. Since then it has also raised more than $700,000 for the Child Cancer Foundation.
Kahlia is the youngest model in the 2013 calendar but not the only Northlander - the cover girl, Arden, and Miss April, Jasmine, are volunteers with the Onerahi Fire Brigade in Whangarei.
Calendars can be bought at www.firemanscalendar.co.nz or from any local fire brigade. The organisers are on the hunt for firefighters for the 2014 calendar, saying Northland men in particular have been shy about putting their names forward. Anyone who thinks they might be model material should contact the New Zealand Firefighters' Sports Association.