Glass railings guarantee maximum transparency. System profiles constituting the supporting structure to accomodate the glass panes can be designed in steel, stainless steel or aluminium (powder-coated or anodised). At the top the glass railings are usually bordered by handrails made of stainless steel round tubes or wood. To increase the filigree and discreet character of the balustrade the handrails can also be realised with filigree U-channel sections. The construction can thus be reduced to its essentials.Glass railings must comply with the legal regulations of the German building authorities according to DIN 18008 (former TRAV = Technical rules for fall protection glazing). The beam load, regulated in the stairs-DIN 18065 is 0,5 kN/lfdm (running metres) for residential buildings. In public buildings the beam load amounts 1,0 kN/lfdm (running metre). Depending on the categorie A, B or C the beam load for the handrail is taken up by the railing posts or by the glass panels themselves. This has an impact on the type and thickness of the glass to be used for the all-glass railing.