Dangerous concrete material RAAC discovered at HMP Northumberland

Reinforced autoclaved aerated concrete (RAAC) has been identified in two cell units at HMP Northumberland, near Acklington.

The prison’s capacity has been reduced by 112 after the units where the concrete was found were closed, allowing work to make the buildings safe to take place. All impacted prisoners have been relocated within HMP Northumberland.

RAAC is a form of lightweight concrete used between the 1950s and 1990s in many public buildings. It has an expected lifespan of around 30 years and is susceptible to structural failure.

More than 200 schools in England containing RAAC were closed or partially closed at short notice in 2023 after a RAAC beam that had been considered low risk collapsed without warning, leading to buildings containing RAAC being considered a safety risk.

An HMP Northumberland spokesperson said: “Following a series of surveys, RAAC has been identified in a few areas at HMP Northumberland.

“We are working closely with the prison service and other specialists to make sure that all appropriate measures remain in place to maintain a safe and secure environment for those who live and work in the prison.

“We can confirm that two small units have been impacted by RAAC (HB3 and 4).

“These have been progressively closed to allow for remedial work, which means that operational capacity has temporarily reduced by 112. However, prisoners affected were relocated within the prison.”

HMP Northumberland is a category C prison with a normal capacity of 1,348 male offenders and is run by private firm Sodexo.