Extract from the Human Rights Commission website: © Australian Human Rights Commission
ISSUE 3:
Nosings on stairways
Importance of the feature
The application of highlighted nosings on treads/goings on stairways assists, in the main, people with a vision impairment; however all members of the community benefit from this application.
The highlighted nosing is used to indicate the location of the nosing or leading edge of the tread/going to ensure safe movement up and down the stairway by all members of the community.
People with a vision impairment may not be able to locate the edge of the tread/going on a stairway if the top of the nosing does not have adequate highlighting to distinguish one tread from the next, thus making it extremely difficult for them to use the steps safely.
To many people with a vision impairment the stairway without this application will look like a ramp or shaded section of a walkway.
Code requirements
The Building Code of Australia (BCA) refers to stairways in D3.3(c) and requires compliance with AS1428.1 for stairways that are required to have access features. The Commission’s view is that all stairways, other than those specifically exempted under the BCA, should have these features for access and safety reasons.
AS 1428.1 specifies technical details such as dimensioning, location and luminance contrast criteria.
Photo 1 shows a stairway with good nosings
Achieving best results
To be effective highlighted nosings must be within the design criteria set out in AS1428.1.
This is achieved by ensuring:
- The minimum luminance contrast to the adjacent tread/going colour is achieved.
- Continuous depth across the full width of every tread/going. The depth of the contrast nosing area must be between 50 – 75mm to ensure its visibility by users. Often we find that 2 x 25mm wide strips have been inserted into the nosings, which have a tendency to be “washed” out by the surrounding tread/going colour.
Common problems and misinterpretations
1. Poorly highlighted nosing on treads/goings
Photo 2
Photo 3
Photo 2 shows an example of the typical view a person with a vision impairment may experience (note no definition between treads/goings). Photo 3 shows the same stairs as seen by a person with 20/20 vision.
Photo 4
Photo 5
Photo 6
Photo7
Photos 4 – 7 show nosing treatments that would not meet the requirements of AS1428.1.
Although the treatment, for example, in photo 4 may meet the criteria in the dry weather it will not in the wet weather as the luminance contrast is lost when the concrete becomes wet.
Photos 5, 6 and 7 are all variations of thin inserts placed in the nosing for slip resistance and will not achieve the required minimum 30% luminance contrast.
Photo 8
Photo 9
Photos 8 and 9 show the required minimum luminance contrast and depth of treatment on the nosings of the treads/goings.