A steel frame is built into the truck. This frame is built in a few centimetres from the wall to be tested. This frame should be well anchored in the truck, as it is responsible for absorbing the reaction forces.
An air cushion is then placed between the wall to be tested and the built-in frame. The air cushion is inflated by means of compressed air.
Based on the surface area of the air cushion and the air pressure present, the load on the wall can be calculated.
If both the plastic and elastic deformations at a certain load remain within the specified limits, the wall can be certified.