A house fire which claimed the lives of a woman and her granddaughter was started when the child's mother left the stove on after using it to spot cannabis.
Bessie Tehuia Tokona, 61, and Eunice Rebecca Jean Felton, 6, both died in the fire at the Housing New Zealand house they shared with nine others on Exeter Cres in Palmerston North on September 3, 2015.
In a report released by Coroner Tim Scott, it has been revealed the child's mother, Nechia Tokona, admitted to leaving the stove on after using the element to spot cannabis.
Specialist fire investigator Michael Finucane completed a report concluding the most likely place for the fire to have started was the two back elements of the stove, which had been left on the high positions.
"Initially flames had reached and melted an extractor fan above the stove," Scott's findings said.
"This caused the motor of the fan to fall from its mountings into or on to the pot at the left-hand rear of the stove. This caused the pot to be dislodged from the stove and fall to the floor, and this caused the fire to spread."
There was evidence a pan of cooking oil was often left on the back left-hand element of the stove with a lid on when not being used.
"It is probable that it was this pan full of cooking oil that started the house fire," Scott said.
The only available evidence of how the pan caught fire was Tokona's evidence she left the element on after spotting cannabis.
"She had no need to turn both elements on to do this . . . I am left to conclude that Nechia turned both the rear elements of the stove on (one by mistake) when she used the stove for spotting cannabis."
There were 11 people living in the house at the time of the fire, and Scott attributed the survival of many of the others to the "prompt, brave and unselfish actions" of Eunice's older brother, who woke to the sound of smoke alarms and woke up other members of the family.
"I stated to the whanau then, and I repeat here, that although the deaths of Bessie and Eunice are a complete tragedy, the whanau can take positives from the tragedy, namely that nine whanau members escaped."
Some whanau members had to break upper-storey windows and jump out to escape, while others went down a wooden fire ladder. They were unable to use the internal staircase because the smoke was too thick.
A second fire-escape ladder had rotted away and never been replaced due to Housing NZ policy to make fire escape routes user-friendly for all people.
"The escape routes from this house were designed to be the two internal stairways and the three doors from the ground storey exiting the house."
The upper windows of the house were sealed with safety latches to prevent children falling out, which was why whanau had to break the windows to escape.
Scott said he could appreciate and understand the reasoning for fire exits to be available for all people, and the reasoning for the safety catches on upstairs windows.
"However while I can understand the reasoning, I do not accept it," he said.
"These policies did not result in any additional fatalities at Exeter Cres but they might have done. Windows needed to be broken and that comes with its own set of issues, and there was only one - and not two fire escapes.
"When it comes to a fire surely the more escape routes the better, even if some of these cannot be used by all people all the time."
Scott also found the fire alarms installed in the house by Housing NZ were not dual-technology alarms, despite the packaging leading Scott, the Fire Service, and Housing NZ to believe they were.
The alarms were ionisation alarms only, which are considered good for detecting flaming fires. The other type of alarm is photoelectric, which is good at detecting smouldering fires.
The fire investigator, Finucane, said he believed the fire most likely started as a fast flaming fire, but because of the behaviour of modern furnishing materials, would have soon turned into a fire producing large volumes of smoke.
Finucane said if an alarm had been placed in the living room near the kitchen, it would have probably sounded quickly after the fire started, before there was much smoke generated.
"It is of course not possible to determine how long after the fire started it was before the alarms were activated and from there before whanau members awoke," Scott said.
"However I think it was highly probable that there was a significant delay before the smoke alarms were activated . . . certainly by the time the whanau members made their escape from the house, the fire was well under way and there was a lot of smoke, suggesting that the fire had well and truly taken hold.
"This in turn suggests that the alarms did not activate for some time after the fire started."
Scott said he had now replaced the alarms in his own home to photoelectric ones as a result of the tragic events at Exeter Cres.
Housing NZ chief operating officer Paul Commons said staff were "extremely saddened" by the tragic deaths, and extended their sympathies to the family.
"We accept the coroner's decision and findings, and acknowledge his comments about our policy in relation to external ladders on two-storeyed properties. It's important to note that when we developed this policy, we took into account a number of factors."
Factors included Housing NZ's "significant investment into new smoke-alarm technology" which is endorsed by the Fire Service, the fact that external ladders were constructed in the 50s and 60s, so their design, structure and materials wouldn't necessarily meet modern standards, and that the ladders aren't a requirement of the Building Code, and are generally not used in other two-storey properties.
"In all our properties, if the farthest point from an exit is greater than 25 metres, we always provide a second means of escape," he said.
"We take the health and safety of our tenants very seriously. Any policy decision we make is made with great care, taking into account wider factors and context."