False alarms are costing Fire and Emergency tens of millions of dollars each year.
This year, FENZ data showed 40 percent of fire alarms attended were false alarms - up from 34% in 2019.
It was difficult to tally up the cost, which depended on whether career or volunteer trucks were sent and the distance travelled to get to alarms, said FENZ risk reduction and investigations manager Pete Gallagher.
But for context, FENZ previously charged businesses $1200 for false alarm responses - and that "wasn't coming close" to the true cost, Gallagher said.
It meant the 33,660 false alarms attended to 12 December this year stacked up to $40,392,000, at the absolute minimum.
"Every false alarm call is probably up in the many thousands of dollars, particularly when you take into account the loss of earnings for the business that's being interrupted by the false alarm," Gallagher said.
They were a big drain on resources, and kept crews from attending actual emergencies, he said.
"As the years go by, and more buildings have connected alarms, our numbers of false alarms are increasing."
The single biggest issue was poor maintenance of older fire alarm systems, and FENZ encouraged building owners to stay on top of it, said Gallagher.
The $1200 charge for false alarms was intended to encourage building owners to improve them - but it was scrapped in 2018 because it was not having the desired effect.
"It became easier to just pay the money rather than to spend the money on upgrading or making the alarm system more reliable."
Curbing the number of false alarms was difficult, because a number of calls were also from members of the public who heard alarms, he said.
"We don't want to discourage that, but on the other hand, we're conscious that there is a large cost associated with attendance of false alarms that can impact our ability to do other things and attend other emergencies."
Better building maintenance would also go some way towards bringing down the number of false alarms, said the Fire Protection Association's David Prosser.
"A significant number of false alarms are caused by water leaks, and dust and dirt, and things within the building," he said.
"There's all sorts of other significant contributory factors, like the activity of occupants in the building, or other contractors working and breaking things, or not knowing what's going on."