#44 Let there be light

Appropriate lighting for roadways and adjacent areas is an essential and integral part of safe system traffic management and design. In many ways, the provision and improvement of lighting touches on the 2025 Australasian Road Safety Conference’s theme of Equity, Elasticity and Evolution. This includes addressing the needs of all road users (Equity), embracing adaptability and promoting mode shift (Elasticity), and addressing safe system gaps through innovations in technology, design, planning and implementation (Evolution).

Benefits

The benefits of appropriate lighting are identified by Austroads[1] and extend beyond road safety to address other community concerns. As well as reducing crash risk for motorists and cyclists, improving the visibility of vulnerable road users, and minimising pedestrian trip hazards, lighting can also improve traffic operation and network performance. Further, it can help to deter crime and improve property security while enhancing the general amenity of public and commercial environments. Internationally, the US Federal Highway Administration (FHWA) reports that lighting can reduce nighttime pedestrian crashes at intersections by up to 42%, rural and urban intersection crashes by up to 38%, and nighttime highway crashes by 28%[2]. In Australasia, similar estimations of nighttime crash reductions are reported by Austroads, as tabulated below.

Evolution of lighting technology in recent decades, including but not limited to the development of LEDs, has brought greater flexibility, precision and control over variables such as colour, glare, spillage into sensitive areas, and effect on the night sky.

Table 1: Estimated reduction in nighttime injury crashes (adapted from Austroads 2021)

Considerations

Provision of roadway lighting usually involves installation of supporting structures such as poles, which potentially represent roadside hazards. These hazards can be mitigated by considering a range of factors, including their location, frangibility, and positive protection such as barriers. Other considerations include potentially detrimental effects of glare, optimal luminance and colours for specific applications, power provision, maintenance requirements, and cost.

[1] Austroads (2021) Guide to Road Design Part 6B: Roadside Environment. Sydney, Austroads.

[2] https://highways.dot.gov/safety/proven-safety-countermeasures/lighting