FAQs on the selection of stair nosings2018-07-26T15:50:52+00:00


There are many misconceptions and misunderstandings with regard to the specification of stair nosing. The FAQs listed below provide the answers and help to clarify the most common issues. A wide range of topics are covered from the use of paints, tapes and hazard warning through to colour, visual contrast and why stair nosings are needed at all.

Why do I need visual contrast?2018-08-03T15:03:51+00:00

Visual contrast between floors and adjacent surfaces, fixtures and furniture is important to enable visually impaired people to differentiate between surfaces, identify features and potential hazards such as changes in levels and obstacles on the floor.

A research project undertaken by Reading University in conjunction with the Royal National Institute of Blind People (RNIB), The Guide Dogs for the Blind Association (GDBA) and ICI Paints first examined the use of colour contrast to aid navigation around the building and identified that highlighting critical surfaces and special features can provide the basis for wayfinding for visually impaired people.

The ‘Colour, Contrast & Perception’ document produced by Reading University uses light reflectance values (LRVs) to measure colour and contrast in products/surfaces and determines whether or not a suitable contrast has been achieved between surfaces.

British Standard BS 8300-2:2018 states that light reflectance values are used to assess visual contrast using the method of measurement detailed in BS 8493:2008+A1:2010. Approved Documents K (ADK) and M (ADM) directly refer to colour and contrast in the definitions section, stating:

‘Contrast visually, when used to indicate the visual perception of one element of the building, or fitting within the building, against another means that the difference in light reflectance value between the two surfaces is greater than 30 points.’

All Gradus stair nosing colours have been measured to provide LRVs in order to provide the specifier with the information needed to ensure that suitable visual contrast is achieved with the surrounding stair material. These values have been determined using the CIE Y value, in accordance with BS 8493:2008.

Good Visual Contrast

picture 1 – Installed with Gradus Stair Nosings

Picture 1 - Installed with Gradus Stair Nosings

Poor Visual Contrast

Picture 2 – No Stair Nosings – Don’t Take the Risk

No Stair Nosings - Don't Take the Risk

Hardnose PVC-u stair nosing and visual contrast2018-08-10T15:19:51+00:00

Gradus Hardnose PVC-u stair nosing provide the ideal solution to creating visual contrast at the step edge. The nosing comprise coloured PVC-u channels and slip-resistant PVC inserts.

Selecting the channel and insert in the same colour provides the ideal solution for creating a single solid band of colour that visually contrasts with the surrounding floor covering. This defines the step edge in line with Approved Documents K (ADK) and M (ADM) of The Building Regulations 2010 and BS 8300-2:2018.

Stair nosing need to highlight the step edge by providing contrast with the remainder of the tread and riser material along the full width of the stair. This is achieved by providing a 30 point difference on the Light Reflectance Value (LRV) scale between the two surfaces – learn more.

All Gradus stair nosing channel and insert colours are measured for LRVs in accordance with BS 8493:A1:2010 to help achieve this difference.

Gradus Hardnose PVCu stair nosing

Selecting the channel and insert in the same colour provides the ideal solution for creating a single solid band of colour that visually contrasts with the surrounding floor covering.


Why do I need stair nosing?2018-07-27T15:39:08+00:00

Research studies have shown that 80% of slips on stairs are likely to occur when users are descending the stairs. This usually occurs as a result of an overstep, when a substantial portion of the foot overhangs the tread. The application of a stair nosing incorporating a slip- resistant material that extends to the leading edge may reduce the risk of slipping.

Stair nosing visually highlight the step edge against the tread and riser surface. Poor delineation of the step edge may confuse people negotiating the stairs, particularly in poor lighting conditions thus increasing the risk of an overstep. The selection of appropriate stair nosing is key to maximising safety and visual clarity of a flight of stairs.

Slip-resistance & Performance

An insert provides a surface that creates friction between the sole of the shoe and the step edge, hence providing slip-resistance and reducing the risk of slip on stairs.

What are LRVs?2018-07-27T15:38:45+00:00

Visual contrast is assessed by comparing light reflectance values (LRVs) of different surfaces. LRVs are a measure of the total quantity of visible light reflected by a surface at all wavelengths and directions when illuminated by a light source.

The LRV scale goes from 0 (all light totally absorbed) to 100 (all light reflected). BS 8493:2008+A1:2010 specifies the method of test to determine light reflectance values of different surfaces of materials. Evidence based research has indicated that a contrast in LRV of 30 points or more will provide good contrast.

Light Reflectance Scale

In order to achieve a suitable contrast between different surfaces, Project Rainbow and ADM recommend that there is at least a 30 point (not 30%) difference in the LRVs of the two surfaces.


Can I specify different colour stair nosing for the top and bottom steps?2018-08-03T15:11:54+00:00

The practice of providing top and bottom stair edgings in a different colour is mainly found in transport environments. It is not a practice that is based on any research or guidance. It is not good practice and could lead to confusion, especially if the top and bottom landing/floor area has yellow hazard lines (similar width to the stair nosing). The user might think that the bottom of the step has been reached at the last white line and that the last yellow stair nosing is actually a hazard line on the level landing/floor area. Gradus does not recommend this practice as it can be confusing and misleading to people with sight loss. Until new research indicates otherwise, all stair nosing on a flight of stairs should be the same colour and show a difference in LRVs of 30 points to that of the floor covering on the remainder of the tread and riser.

Do you need stair nosing when you have a lift?2018-07-27T15:44:45+00:00

Building owners have a legal duty to ensure all people can gain access to and use a building and its facilities. People should be able to choose between using the lift or stairs. It may be interpreted as “discrimination” under the Equality Act 2010, if people with say sight loss had to use a lift rather than the stairs? Therefore visual contrast must be provided on stairs to reduce the risk of a slip or trip and ensure safe access to and use of buildings. In the event of a fire evacuation, lifts should not be used.

Hazard warning / shark tooth insert2018-07-27T15:21:39+00:00

Research has shown that patterned highlighting such as hazard warning or shark tooth should be avoided as it can mimic the visual image experienced by some visually impaired people and lead to confusing and conflicting messages.

Tapes and paints on stairs2018-07-27T15:20:08+00:00

Adhesive tapes and paints are not recommended on steps as they are not regarded as permanent and if not securely fixed, may become a trip hazard.