9.2.1 Road Safety Audit (RSA) has existed in the UK since the late 1980s. Audits of trunk road and motorway schemes have been mandatory since 1991.


Many local authorities voluntarily carry out such design-independent audits using the trunk road standard contained in the Design Manual for Roads and Bridges HD 19/03 (DfT 2003) or the guidance given in the IHT document The Safety Audit of Highways [IHT 1996].

Other helpful documents on the basics of RSA practice include the book Practical Road Safety Auditing [TMS 2001].

Under the HD19/03 standard the RSA process audits at four key stages:

1. Preliminary design stage.
2. Detailed design stage (prior to starting construction).
3. Prior to opening to traffic (or after finishing construction if it is not possible to keep the scheme closed to traffic).
4. One and three years after opening.

9.2.2 Highway and traffic engineering practice in England and Wales usually separates safety auditing and user auditing.

The latter focuses on encouraging better infrastructure provision for sustainable modes to encourage modal shift. However, it has always been good practice for safety auditors to take a multi-modal approach to the process, taking special care with safety implications for vulnerable road users; equestrians, cyclists and pedestrians. While not being completely overlooked, motorcyclists have had a lower profile in this ”special care” regime, perhaps because the higher speeds of motorcycles push them, almost intuitively, into the same camp as twin track motor vehicles.

This is a serious misapprehension.

The dynamics of motorcycles and the vulnerability of their riders make motorcycling a unique mode in the traffic mix, demanding separate, informed consideration by designers and auditors alike.

9.2.3 No one expects special treatment for motorcycles and their riders. It will always be the safety auditor’s prime objective to examine the safety of a new scheme from a holistic viewpoint.

The RSA practitioner seeks an optimal balance of risk across all modes, using experiential and empirical judgement to identify hazards, quantify risks and estimate likely outcomes, both in terms of numbers and severity.

9.2.4 The point of this chapter is not to present motorcycles as a special case, but to redress an imbalance among RSA practitioners, with little or no experience of riding a motorcycle, of how the balance of risks shifts markedly on two wheels as opposed to four or more.