Rooms may be used as workrooms only if their light ingress surfaces which must lead directly to the exterior correspond to at least 10% of the floor area of the room. Exceptions are workrooms that are used only temporarily (i.e. copying rooms) as well as certain types of rooms, such as booths for master craftsmen or porter´s lodges and cashier’s desks. The provisions relating to light ingress areas apply, in particular, to workrooms with permanent workplaces.
