Reinforced autoclaved aerated concrete (RAAC) is a building material that was popular in the second half of the 20th century. Lightweight, affordable, and easy to install, RAAC was used in the construction of a number of public buildings across the UK and mainland Europe. Unfortunately for the people who frequent those buildings, there is growing concern that this material may no longer be safe to use. In fact, some experts have suggested that RAAC is so much weaker than standard concrete that it should not even have the word 'concrete' in its name.
Intrigued? Check out this gallery to find out more about RAAC and why it can be dangerous.