Eleven fire trucks and career and volunteer firefighters fought the fire which occured around at 5.13pm.
It took them 45 minutes to extinguish the fire in three laundry bins. Two teams cut a hole in the roof to help ventilate the room.
Most of the damage was caused by smoke. The fire was limited to the laundry room.
A Department of Corrective Services spokesman said it began when very warm linen tightly packed in the clothing bins began to smoulder.
Fire alarms were activated and DFES attended. The WA Police arson squad determined the blaze it to be accidental involving no suspicious activity.
‘Today, the prison is commencing clean-up and laundry operations will be returning to normal shortly,’ the spokesman said last Thursday.
‘This incident caused no disruption to normal prison operations.’
Meanwhile, Corrective Services Minister Joe Francis conducted a surprise inspection of recently damaged cells at Hakea Prison, using his powers under the Prisons Act.
He was reportedly told of the damage 10 days after it had occurred.
The damaged cells were in the section that was set up to house juveniles from Banksia Hill Detention Centre after significant damage was caused in a riot at Banksia Hill Detention Centre earlier this year.
The Department of Corrective Services spokesman confirmed on Thursday that four cells were deliberately damaged by detainees at the Hakea Juvenile Detention Centre on three different dates in four separate incidents.
‘The damage was varied over the four cells but included damaged shelving, toilets and shower screens and observation windows,’ he said.
Repairs are estimated to cost $7500.