This paper presents the findings of the Review of the Lighting of Rural Roundabouts DoT project, to review methods of reducing light pollution from trunk road lighting. At present, most roundabouts on British roads are fully lit, even if the adjoining roads are not lit. As British Standard BS 5489 Part 4 provides the code of practice for lighting single-level road junctions, including roundabouts, the project first investigated how it was interpreted in practice. 117 roundabouts were selected, of which 104 were lit trunk road roundabouts, ten were unlit, and three were other roundabouts with non-standard lighting. A questionnaire survey about these roundabouts was sent to the relevant local authorities. Taking account of the information collected, the Project then analysed lighting policy and specifications, together with data about accidents at roundabouts. In particular, it analysed and decided to accept the arguments in favour of lighting rural roundabouts. The findings of the survey and analyses were then combined to formulate possible changes to BS 5489 Part 4, as applied to rural roundabouts, which could lead to reductions in light pollution and lighting costs.
Abstract