The Northern Territory government has been urged to address "inhumane" conditions at Alice Springs Correctional Centre (ASCC) in the wake of an attempted escape by fifteen prisoners on Boxing Day.

The Justice Reform Initiative (JRI) said around 15 people attempted to escape their cells during a heatwave on Boxing Day, when the temperatures outside reached 37 degrees Celsius, and the cells do not have air-conditioning units.

"The incident on Boxing Day highlights the pressing need for immediate action to address these inhumane conditions, particularly during times of extreme heat," JRI board member and patron Olga Havnen said.

The prison, which is considered overcrowded and lacking in infrastructure, has been described by United Workers Union secretary Erina Early as a "very hot box."

JRI argued the lack of air-conditioning puts both prisoners and staff at risk and this was repeated by Ms Early, who told the ABC staffing and infrastructure at the jail needed to be addressed immediately.

"We've still got big things to do with fatigue, work health and safety, overcrowding," she said.

In 2018, a riot at the facility resulted in prisoners being tear-gassed as they experienced temperatures over 40C.

Ms Havnen, a prominent Indigenous leader in the NT, said it was not a matter that could wait until after a tragedy had occurred.

"The 2018 riot, triggered by similar conditions, serves as a stark reminder of the urgency in addressing this issue," she said.

"The government must move beyond mere lip service and provide a concrete timeline for improving conditions within the prison."

In 2022, the NT ombudsman called for air-conditioning to be installed at the facility, warning extreme heat was only likely to be exacerbated due to climate change. However the NT Corrections Commissioner said at the time there were no immediate plans for cooling systems to be implemented at either Alice Spring or in Darwin, due to "extreme cost implications".

Currently the NT has the highest levels of incarceration in the country and over 85 per cent of all inmates are Indigenous. Ms Havnen said that whilst reducing prison numbers was critical to address the issue of overcrowding, the current conditions had to be immediately improved.

"Temperatures in Alice Springs routinely soared above 35 degrees in December, putting the wellbeing of those being held all day in maximum security cells at risk," she said.

"We are already funnelling too many people into harmful prison settings – but it is even more unacceptable to hold people in conditions that are dangerous and inhumane."

Ms Havnen said community organisations - particularly those led by Indigenous groups - had been forced to repeatedly sound the alarm about the conditions in Alice Springs, and other prisons that suffered from inhumane conditions.

Roebourne prison in the Pilbra was repeatedly criticised for its lack of air-conditioning in the facility, in a town that reached over 50C in early 2022, and with the majority of inmates being First Nations. The conditions were likened to torture, with one former inmate noting prisoners needed to flood their cells in order not to burn.

The WA government committed to implementing cooling facilities after a sustained campaign from Indigenous, community and health groups, but not before 2024.

"Roebourne in Western Australia, which had similar concerns, has already committed to installing air conditioning and the NT Government needs to do the same at Alice Springs as a matter of urgency," Ms Havnen said.

"Failing to act promptly jeopardises the health and safety of both those being held there and staff working there."

A NT government spokesperson told National Indigenous Times they were monitoring temperature levels and additional cold drinking water supplies are available.

"We are trialling a new style cooling fan in one area of the jail and will implement these if successful in reducing the temperature," the spokesperson said.

The government has also commissioned consultants to assess how to cool the prison. The recommendations are currently being "costed" and will be considered this year.