The Q-Range of Stair Nosings has a selection of UPVC profiles that are available in 14 different colours. By selecting tread material the same colour as the uPVC carrier the resulting completed Stair Nosing is a continuous band of the same colour. This is a principle requirement of current Buildng Regulation guidelines and means that by chosing a Stair Nosing colour that is at least 30 LRV points different from the stair floorcovering, this guidelines is met.. Q-Range Stair Nosings help make stairs safer in ascent or descent. The Q-range is a patented design. The choice of profiles cover gauges from no floorcovering to 7mm.