Inmates in Roebourne regional prison are still in cells without air conditioning in extreme heat, the Aboriginal Legal Service of WA said on Monday.

The ALS noted that when Roebourne temperatures soared to "over 50 tortuous degrees" during the summer of 2022, the Western Australian government announced in November that year that $10 million dollars would be provided for air-conditioning to be installed in every cell at Roebourne Regional Prison.

Last December, with the tender process ending on 3 January this year, the ALS wrote to WA Corrective Services Minister Paul Papalia seeking an update.

On Monday, as the temperature soared to 43 C in Roebourne, the Service revealed the "distressing outcome" is that prisoners are still living in cells without air-conditioning, in "conditions that could prove fatal from heat stress or heat stroke".

ALS WA chief executive Wayne Nannup said that given record temperatures following extreme heat in the Pilbara this summer, "the relentless heat places the lives of inmates at great risk and the government cannot drop the ball given the failure of the tender process".

"It needs to find a way, and quickly, to ensure that air conditioning is installed as a matter of urgency," he said.

ALSWA remains "extremely concerned" about any further delays in the installation of air conditioning at RRP and urges the government to act swiftly.

"WA cannot continue to wait and watch as the inmates stay locked up in such unacceptable, inhumane and life threatening conditions," said Mr Nannup.

A WA Department of Justice spokesperson told National Indigenous Times that the tender process for the installation of air conditioning in the main accommodation units at Roebourne Regional Prison "is in progress".

"The Department of Justice has a number of measures in place at the prison to manage heat risks. This includes fans in every cell, air-conditioning in the recreation hall, prisoner visits area and female activities area, and shade structures in the main areas of the prison," they said.

"There are also a number of air-conditioned cells available for prisoners with medical conditions. The prison maintains a flexible routine to adjust to the conditions and ensures all planned recreational activities are closely supervised. Cell temperatures are monitored through the day in the accommodation units and medical staff are on duty to ensure prisoners' health and safety."