DIN EN 13300 replaces the former DIN 53778 and divides interior colours according to various properties. One property here is wet abrasion resistance, i.e. the washing and abrasion resistance of the paint, which is divided into 5 classes. Class 1 represents the highest wet abrasion resistance, class 5 the lowest. In addition, descriptive terms from the old DIN 53778 are still in use, e.g. "abrasion-resistant" for paints of wet abrasion class 2 and "wash-resistant" for paints of wet abrasion class 3.
Source: bauwion
