Firefighters want an inquiry into a fatal house fire in Ōtaki to determine whether the fastest, best-equipped fire truck went and if there is a wider problem.
Volunteer firefighters got to the house in 15 minutes on 21 July and pulled two people out, but both died in hospital later.
While several other volunteer trucks got there within minutes, the full-time Paraparaumu fire engine was not called until two hours later.
The Professional Firefighters' Union (PFU) is calling for an investigation into why the truck seems to have been sidelined.
"Why was the quickest/fastest appliance ... removed on certain PDAs [pre-determined attendances] on the coast and for what reasons?" a Paraparaumu officer asked on 10 September in emails RNZ has obtained.
"Who made that decision, when it was made and [what was] the basis for that decision?" the PFU asked Fire and Emergency.
National secretary Wattie Watson said it was not suggesting the fatalities could have been avoided, but the stakes for the community were too high not to ask the question.
FENZ told the union: "There was no error in the way this call was handled."
It also told RNZ on Monday: "We dispatch crews who can respond the fastest to an incident whether they are volunteer or career."
The agency had analysed the Ōtaki response, but might take another look at it, region manager Bruce Stubbs said.
The volunteer and full-time brigades in Kāpiti overlap.
Documents show the volunteers have resisted changes to response plans - made as highway layouts changed - in 2018 and again in 2020.
Volunteers had been told there was no problem with their response times or skills, so saw the proposal as an affront.
"We don't want paid crews anywhere near here," one volunteer Waikanae officer was quoted saying in 2020.
The United Fire Brigades Association (UFBA), that represents volunteers, said that was all sorted out back then, and it had not lobbied recently for changes to what trucks went where.
It rejected the PFU's call for an investigation.
"By all accounts, and some of it anecdotally, I understand it went really well, they actually did effect a rescue and got two elderly people out of the property," UFBA chief executive Bill Butzbach said.
The chief fire officers at both Waikanae and Ōtaki both declined to comment.
FENZ said the Ōtaki volunteer brigade who made the rescue, and the full-time Paraparaumu Fire Station had the same breathing apparatus for their crews.
But the professionals' union said an investigation had to look into if the Kāpiti response plan had been changed.
If a problem was exposed, that should trigger a closer look "to prevent critical decisions being made on a parochial basis in the future, regardless of the district", Watson told Stubbs.
FENZ told RNZ it had regularly reassessed the Kāpiti response plan as road layouts changed - three stretches of new highway have opened since 2017.
Documents and emails around the change proposal in 2020 show one professional firefighter saying: "A few have tried to get this over the line and failed."
The proposal essentially envisaged Paraparaumu's full-time engine being the routine second truck at a fire, to supplement the volunteer response, as opposed to a second volunteer fire engine.
The Waikanae brigade said the proposal's benefit would be "marginal - maybe a few seconds either way" getting to an emergency, and was counter-productive.
"It is utterly soul destroying to a trained volunteer when an emergency does occur locally and the career resource is preferred, responded and utilised in preference," they said.
"The long-term effect is that volunteers won't offer their time in preference and will resign."
Another note said: "Otaki agrees with this and there was a fear raised that if staff know a paid truck is coming they may consider not responding due to being busy at work."
An assistant commander replied that the proposal was "in no way designed to belittle, reduce or change what volunteers do for their communities".
It was about full-time crews "enhancing" volunteer efforts.
"There is no more my patch vs your patch, our thinking needs to change," he said.
Another of the region's volunteer chiefs commented: "We all need to take a good long look at ourselves to work in together and back each other up for the greater good."
A firefighter told RNZ that even single minutes counted, when going to a cardiac arrest.
The emails show the United Fire Brigades Association complained in March 2020, but FENZ told RNZ on Monday the complaint was resolved, and the proposal implemented.
Butzbach said full-time crews were there to support volunteers who made up 86 percent of firefighters.
"By and large, they get on really well," he said.
New highways can pose problems with limited exit or u-turn points for fire engines. Toll roads, typically, have even fewer options, and the government wants more toll roads.
FENZ said there had been formal talks about this at a national level, however, locally, plans were made as road access changed.
Where there were median barriers, fire engines were sent from either end of a highway.
At Kāpiti-Ōtaki, emergency access points made things easier, it said.