The possible mechanical stress of an interior door is divided into four classes according to RAL-GZ 426:
The assignment of an element to one of the load classes requires the passing of tests according to DIN EN 947 (resistance to vertical loads), DIN EN 948 (resistance to static torsion), DIN EN 949 (resistance of doors to impact of a soft and heavy impact body) and DIN EN 950 (resistance to hard impact). Different test criteria apply to the different load classes.
Source: bauwion
