Prisoners forced to live in cells during a scorching Red Centre heatwave should be allowed access to air-conditioning as a human right, a Territory union leader says.

Key points: NT Corrections say there were no injuries in a riot which saw tear gas used on Alice Springs prisoners

NT Corrections say there were no injuries in a riot which saw tear gas used on Alice Springs prisoners United Voice NT warns there will be more riots if cells are left without air-conditioning

United Voice NT warns there will be more riots if cells are left without air-conditioning An investigation into the incident commenced yesterday, with security beefed up at the prison

The call comes two days after prisoners were tear gassed during a riot in Alice Springs Correctional Centre, initially sparked because of plus-40C temperatures baking Central Australia.

According to a statement released yesterday by NT Corrections Commissioner Scott McNairn, the prisoners had refused to return to their accommodation cells due to the heat on Saturday.

"Officers negotiated and permitted prisoners to stay in the open court yard of the accommodation block where there is better airflow," Mr McNairn said.

"Some prisoners took the opportunity to cause a disturbance and began damaging property.

"Once attempts to negotiate those prisoners back into their cells failed, chemical spray was used in accordance with standard procedure to subdue them and swiftly bring the situation under control."

Call for air-conditioning in cells

Alice Springs Correctional Centre was the scene of a riot on Saturday. ( CASA )

Conditions at the ageing prison are "inhumane" for prisoners living through such heat, Erina Early, the branch secretary of United Voice Northern Territory, said.

"Basically at the moment the dorms are built for eight prisoners; they've got two toilets and two showers, and at the moment you've got 16 prisoners to a dorm," Ms Early said.

"It's been a matter that we have been arguing with the department for quite a long time because the conditions are inhumane, especially when you've got so many prisoners in one room and the prison is not designed for it."

The men's section of the prison doesn't have air-conditioning, Ms Early said, and the extraction fans were broken, "so there's no circulation at all in the prison".

"With the 50-degree heat, being overcrowded, basically there's a huge risk and potential for prisoners to basically kick off."

Fears situation will be repeated

Ms Early said she believed a riot could "absolutely" happen again if nothing was changed.

"To me the only way that this is going to be fixed if there is appropriate cooling mechanisms for the prisoners, because it's not humane in a room crammed together, where you've only got minimal toilets and also no air-conditioning.

"So they really need to address the overstaffing and the conditions of the actual cells."

The notorious Alice Springs prison has been under fire for the past few years, for overcrowding, riots and a number of prison escapes.

The Commissioner's statement said NT Police were made aware of Saturday's disturbance but were not deployed to attend the situation.

"No injuries were sustained by prisoners or staff during the incident and the disturbance was contained within the remand accommodation unit," Mr McNairn's statement said.

An investigation into the incident commenced yesterday and prison security was bolstered following the incident.

NT Police Deputy Commissioner Michael Murphy told ABC Local Radio he would await to see if Corrections put forward any "criminal referrals" from the incident.

"[If that happens] we'll conduct an investigation and work through that process and lay any charges when the evidence is there," he said.