When the hinges are visible:

1. We stand in front of the door to see the hinges. If we see them on the left then it means that these are the DIN-left doors, and if on the right - DIN-right.

When the hinges are invisible:

1. We stand in front of the door so they open "to us". If the hinge is on the left, these are the DIN-left doors, and if on the right - DIN-right.

2. We are facing the door in front of the hinges. If the door opens to the right, these are the DIN-right doors, and if to the left - DIN-left.