A key requirement for balustrades or barriers is that they should be constructed such that a person cannot fall over or through them.
A key requirement for balustrades or barriers is that they should be constructed such that a person cannot fall over or through them. At the same time they must restrict the potential for a child to crawl through them. Openings in balustrades or barriers must be constructed so that any opening does not permit a 125mm sphere to pass through it where for stairs this space is tested above the nosing line. For architects designing a stair, moving a circular block over the plan will help in determining whether any 125mm circular gap may exist.
In structural terms, the barrier should be strong enough to resist collapse in the case of a user falling or leaning against it. A balustrade or barrier must be designed to take loading forces in accordance with AS 1170.1 which requires that a balustrade or barrier should be structurally adequate to withstand a point load of 0.6kN and an evenly distributed load of 0.4kN applied inward, outward, or downward on the handrail. In commercial situations the potential loads may be much higher. Each of the technical data sheets associated with Arden's signature glass balustrade style contains specific recommendations for load requirements and glass spans.
The intentions of specifying design loads is to ensure that the barrier is rigid enough to withstand a person falling against it without collapsing (point load), and also is rigid and strong enough not to collapse should people lean against the barrier (distributed load). In crowd situations this is potentially a very high load, and Arden always consults with builders as to the intended design load. The installation situation, whether at a stadium, restaurant, or office, obviously has a big impact on how high a design load to achieve.
For floors more than 4m above ground, any horizontal elements within the balustrade or barrier between 150mm and 760mm above floor must not facilitate climbing. To prevent this ideally, the balustrade should have vertical members spaced no more than the maximum opening or be a solid panel barrier. This requirement may preclude the use of horizontal battens in these installation situations.
Published on: 28-Sep-2010. Topic/s: Stair safety, compliance, and regulations