Lighting guide for inclusive design

Background

Why is lighting so important?

Good lighting plays an important role in the aesthetic appeal of an environment. It also benefits people with vision or hearing impairments, helping their mobility and ability to identify features and facilities.

Universal/Inclusive design issues

Many people who are blind or partially sighted have a degree of residual vision. Environments that encourage people to optimise their remaining or residual vision are critical in the design of inclusive environments.

Design principles

Types of lighting

Lighting must provide a comfortable, safe and healthy environment. Determining the appropriate lamp, luminaire, and direction of light depends on the purpose of the lighting. Is it intended to create ambient (ie general), task, or accent lighting?

• Lamps (ie light sources), used in luminaires, include incandescent, fluorescent and high-intensity discharge
• Luminaires (ie fixtures) may be surface mounted, recessed, suspended, track, structural, portable or integrated with furniture
• Lighting types include: incandescent, fluorescent and LEDs

Healthy lighting

Lighting design is recognised as a key factor in health and wellbeing. Poor lighting can cause eye strain, headaches and/or affect human emotions. Flickering lights can trigger epileptic seizures.

The quality and type of light influences an internal effect known as the ’circadian clock’ which relates to human perception of light during a daily cycle. This biological clock is synchronised by several environmental factors, including light, temperature, hormones and other socially based cues. Lighting design directly impacts circadian rhythms.

Lux levels – Lighting

These are set down in AS 1680.0:2009 Interior Lighting – Safe Movement.

Lux levels – Paths of travel

AS 4299—1995 Adaptable housing requires an even degree of light throughout the building, particularly along paths of travel (Clause 3.6).
A level of illuminance should be provided to comply with AS 1680.1—2006 and as per the recommended illumination levels for people with vision impairment for different rooms shown in Table 3.1 of AS 1680.1—2006.

Safety and secure lighting

Provide a minimum lighting level of 50 lux at ground level and ‘light fittings should light up the surface for one metre on each side of the path’ (AS 4299—1995 Clause 3.6).

Glare

Glare is a vision impairment produced by intense light, and it can occur either directly or by reflection. It occurs whenever there is a high contrast between a light source and the particular object a person is looking at.

Two types of glare that can affect people’s vision include:

• Discomfort glare when there is a bright light source within the field of view. This is particularly obvious in a dark passageway terminating in a large window at the end of the view. One technique is to design a projecting hood or screen to moderate the impact of the contrast.
• Disability glare when the source of glare is very bright and centrally positioned in the field of vision. This can be overcome by the use of low-reflectance materials or by re-arranging and/or re-positioning the viewing direction of the surface.

Controls

Automatic sensor operated controls are preferred. Sockets, switches and controls are acceptable but should be readily identifiable. Good environmental design allows people to alter their space, so ideally manual overrides would be available and intuitive to use. The minimum illuminance at switches, sockets and controls should be 100 lux.

Incorporate rocker action and toggle switch types with a minimum dimension of 30mm x 30mm; push pad switches shall have a minimum dimension of 25mm diameter and be raised above the surface of adjacent finishes.

Switch plates should be positioned at a height between 900mm and 1100mm above floor level, as per AS 1428.1—2009 Design for access and mobility.
Ensure clear colour and luminance contrast of controls and any signage with backgrounds.

Emergency lighting and safety

At night or in dark areas, where risk is perceived to be high, lighting can impart an increased sense of safety and wellbeing. It is possible to reduce concerns of physical danger. It is also appropriate to reduce risks such as tripping and falling.

Note: Various international studies indicate that high levels of night lighting have not correlated to a reduction in crime. However, street light reduction should be handled carefully as concerns have also been expressed that 'some felt less safe, and some felt that a ‘public good’ had been removed'. (Refer Environment note: Light pollution)

It is important to reduce feelings of uncertainty, insecurity and apprehension when experiencing lonely or empty environments, or poorly illuminated steps, ramps or uneven surfaces.

Lighting design must identify potential hazards, instil feelings of confidence and comfort for all users, as well as reducing risks of injury. This is especially important for people with reduced vision.

Exteriors

Principles set out in this guide note apply equally to exterior spaces. Landscape areas and carparks require lighting to achieve well-lit safe paths of travel. Hazardous elements must be clearly illuminated.

Wayfinding

Wayfinding is the ability to navigate through unfamiliar territory. Users compile a cognitive map to orientate themselves and navigate around a building and locate specific places. Various methods assist in wayfinding, including building design, signage, tactile maps, audible directions, colour or contrasts, tactile finishes and lighting. Lighting can be a positive factor in identifying and reinforcing a route or pathway.

Contrast

Walls and floors should have distinct luminance and colour contrast between them.
In accordance with AS 1428.1—2009 Clause 13.1, all doors/frames shall have a minimum luminance contrast of 30% to adjacent walls.

Hazardous elements – Stairs

Ensure good lighting to all stairs and landings and provide luminance contrasting strips to all tread nosings (Refer AS 1428.1—2009 Clause 11.1).

Unmarked glazing

‘All frameless or fully glazed doors, sidelights including any glazing capable of being mistaken for a doorway or opening shall be clearly marked for their full width with a solid and non-transparent contrasting line. The contrasting line shall be not less than 75mm wide and extend for the full width of the glazed panel. The lower edge of the contrasting line should be located and set between 900mm and 1000mm above the plane of the finished floor level.’ (AS 1428.1—2009 Clause 6.6).

Ensure a minimum of 30% luminance contrast when viewed against surfaces within 2m of the glazing on the opposite side.

Further reading

National Construction Code (NCC)/Building Code of Australia (BCA) – current year of adoption

Australian Standards:

• AS 1428 Suite of standards
• AS 4299 – Adaptable housing
• AS 1735.12 Lifts, escalators and moving walks, Part 12 Facilities for persons with disabilities
• AS 1680 – Interior and workplace lighting

International Standard:

• ISO/FDIS 21542, Building construction - Accessibility and usability of the built environments

Acknowledgements

The Australian Institute of Architects' National Access Work Group kindly contributed to the content of this note – special acknowledgement is made of NAWG member, Brian Kidd, who sadly passed away before this note was completed.