Australian Standards AS 1428.1-2009 Design for access and mobility-General requirements for access - New building work specifies a minimum of 30% luminance contrast requirement between the stair nosing and the surrounding substrate colour. This assists all pedestrians, especially those with visual impairment, to safely navigate the edge of the step. Highlighting the nosing on steps is important for all stairs but stairs which are poorly lit e.g. (fire stairs and external stairs at night) are of significant danger to pedestrians.
In basic terms, a product with dimensions ranging between 50 - 75mm on the tread and not greater than 10mm on the riser, while offering a minimum of 30% contrast to the surrounds, is required.
Why only 10mm on the front riser ?
We have literally had hundreds of people ask this question to us over the last decade. The simple answer is that while contrast is a good thing on the tread of a step, it is detrimental on the riser as it may confuse pedestrians causing them to misstep/trip/fall. Put another way, to navigate a set of stairs, a pedestrian must place their foot on the nosing of each step. The nosing must offer contrast (30%) to the surrounding substrate colour to highlight the 'stepping zone' to the pedestrian. If the riser (vertical face) of the stair is also highlighted, an ascending pedestrian might mistake this for the area which they are to place their foot resulting in a trip and/or fall.
'Legacy' stair nosing which have noses/front returns longer than 10mm (say 30mm for example) are still in circulation (we still produce one too) but they should only be used in very special circumstances and may need to be specially coloured to blend in with the surrounding substrate colours.
For more information and specific project recommendations; including LVR data, testing services for samples and LVR calculations - please contact us.