Road Safety Audits: What Developers Need to Know

Road Safety Audits (RSAs) are one of those requirements that developers frequently encounter but often misunderstand. They appear in planning conditions, in highway authority responses, and in Section 278 technical submissions — but the detail of what they involve, who can carry them out, and what happens when issues are found is rarely well understood outside the highways engineering profession.

This article explains the RSA process from a developer’s perspective: what the four stages are, when each is required, and how to manage the audit process efficiently so it does not become a bottleneck in your programme.

What Is a Road Safety Audit?

A Road Safety Audit is an independent, systematic assessment of a highway scheme to identify potential road safety problems that could affect any road user — drivers, pedestrians, cyclists, motorcyclists, and equestrians. The audit is carried out by a team of qualified professionals who are independent of the design team, ensuring an objective review.

RSAs are governed in England and Wales by HD 19/15 (now GG 119 under the Design Manual for Roads and Bridges) and in Scotland by equivalent guidance. The overarching principle is straightforward: identify safety issues early, when they are cheapest and easiest to resolve, rather than after the road is built and accidents have occurred.

An RSA is not a design check. It does not assess whether the design complies with standards or whether the engineering is sound. It focuses solely on road safety — specifically, whether any aspect of the design could lead to collisions or injuries. This distinction matters because a design can be fully compliant with standards and still have safety deficiencies that an RSA will identify.

The Four Stages

Road Safety Audits are carried out at four stages during the lifecycle of a highway scheme. Not all stages are required for every scheme — the highway authority will specify which stages are needed based on the nature and scale of the works.

Stage 1: Preliminary Design

A Stage 1 RSA is carried out at the preliminary design stage, when the general layout and alignment have been established but before detailed design begins. At this stage, the audit team reviews:

• The general layout, including junction type, road alignment, and access arrangements.
• Visibility and sight lines.
• Pedestrian and cyclist provision.
• Interaction with existing highway features.
• Speed environment and its relationship to the proposed design.

A Stage 1 audit typically reviews drawings at 1:500 or 1:1000 scale, together with a design brief and any relevant traffic data. The audit team will also carry out a site visit to understand the existing conditions, traffic movements, and any site-specific factors that the drawings may not capture.

The value of a Stage 1 audit is that it catches fundamental layout issues — such as poor junction visibility, inappropriate access locations, or missing pedestrian facilities — before the design team has invested significant effort in detailed design. Changes at this stage are inexpensive and straightforward; the same changes at Stage 2 or later can be costly and disruptive.

Stage 2: Detailed Design

A Stage 2 RSA is carried out when the detailed design is substantially complete — typically at the stage when drawings are being submitted for technical approval. The audit team reviews:

• Detailed layout drawings, including carriageway widths, kerb lines, footways, cycleways, and crossing points.
• Signing and road markings.
• Lighting design.
• Drainage and the potential for standing water on the carriageway.
• Traffic signal design (if applicable).
• Construction phasing and temporary works.

Stage 2 is usually the most detailed and intensive audit. The audit team will review all available drawings, specifications, and supporting documents, and will carry out a further site visit (or confirm that conditions have not changed since the Stage 1 visit).

For most development-related highway schemes — new site accesses, junction improvements, pedestrian crossings — Stages 1 and 2 are the minimum requirement. Many highway authorities will require both before granting technical approval for Section 278 works.

Stage 3: Construction

A Stage 3 RSA is carried out during the construction phase, before the scheme is opened to traffic. The audit team visits the site to assess:

• Whether the scheme has been built in accordance with the audited design.
• Any safety issues arising from the as-built conditions that were not apparent from the drawings.
• Temporary traffic management arrangements and their impact on road safety.
• Night-time conditions, including the effectiveness of lighting and the visibility of signs and markings.

Stage 3 audits are less commonly required for smaller development schemes but are standard for larger highway projects, particularly those involving traffic signals, roundabouts, or significant changes to road alignment.

Stage 4: Post-Opening Monitoring

A Stage 4 RSA is carried out 12 months after the scheme is opened to traffic. It assesses the safety performance of the completed scheme using collision data, traffic observations, and a site visit. The purpose is to identify any safety issues that have emerged in practice — for example, unexpected turning movements, pedestrian desire lines that were not anticipated, or problems with surface water drainage during actual storm events.

Stage 4 audits are relatively rare for development schemes but are important for major highway projects where the long-term safety performance needs to be monitored.

When Are RSAs Required?

The requirement for an RSA is determined by the highway authority, usually during the planning process or at the pre-application stage. As a general rule:

• New site accesses onto existing highways: Stage 1 and Stage 2 RSAs are almost always required as part of the Section 278 technical approval process.
• Junction improvements and traffic calming: Stage 1 and Stage 2 are required; Stage 3 may also be required for more complex schemes.
• New estate roads: RSAs are not always required for internal estate roads that will be adopted under Section 38, but some highway authorities do request them, particularly for layouts with unusual geometry or where the speed environment is a concern.
• Planning conditions: Some planning consents include conditions requiring RSAs to be completed and submitted before works commence. Check your planning conditions carefully — if an RSA is required, it must be carried out by a qualified, independent team before you can discharge the condition.

If you are unsure whether an RSA is required, ask the highway authority early. Including an RSA in your programme from the outset is far better than discovering the requirement at the technical approval stage and having to pause the process while it is carried out.

Who Can Carry Out an RSA?

RSA team members must be independent of the design team and must hold appropriate qualifications. In England, this means:

• The audit team leader must hold a certificate of competency in Road Safety Audit, as defined by GG 119 (formerly HD 19/15).
• The team must include at least two members, with appropriate experience in highway design, traffic engineering, and road safety.
• No member of the audit team can have been involved in the design of the scheme being audited.

This independence requirement is absolute. You cannot audit your own design, and the highway authority will reject an RSA carried out by a team that has any involvement in the scheme design. If your highways consultant is also the designer, you will need to appoint a separate RSA team.

Some highway authorities maintain lists of approved RSA practitioners, while others accept any team that meets the competency requirements. Check with the authority before appointing an audit team.

What Happens When Problems Are Found?

The RSA team records its findings in a formal RSA report, which is submitted to the highway authority (the “overseeing organisation” in DMRB terminology) and the design team. Each finding is described as a “problem” and is categorised based on its potential severity.

The design team must then prepare a formal “Designer’s Response” to each problem, which falls into one of three categories:

1. Accept and amend the design: The designer agrees with the finding and modifies the design to address the safety concern.
2. Accept but propose an alternative measure: The designer agrees with the finding but proposes a different solution to the one suggested by the audit team.
3. Reject with justification: The designer disagrees with the finding and provides a reasoned justification for not amending the design.

Importantly, the decision on whether to accept or reject a finding does not rest with the audit team or the design team alone. It is the highway authority — as the overseeing organisation — that makes the final decision on how each finding is addressed. In practice, most authorities expect findings to be addressed unless there is a compelling reason not to.

Rejecting audit findings without robust justification is risky. If a collision subsequently occurs at the location identified in the audit, the rejected finding becomes a significant liability issue. We always advise clients to take audit findings seriously and to address them wherever practicable.

Managing RSAs Efficiently

RSAs do not need to be a bottleneck, but they do require planning. Here are some practical tips:

Programme them early. An RSA takes two to four weeks from appointment to report delivery, depending on the team’s availability and the complexity of the scheme. If you wait until the design is finished before thinking about the audit, you will add a month to your programme.

Provide complete information. The audit team can only audit what they can see. Incomplete drawings, missing traffic data, or a lack of context about the surrounding highway network will result in a slower, less focused audit and potentially more findings that could have been avoided.

Carry out a site visit with the audit team. While not always required, a joint site visit with the designer and the audit team can help the auditors understand the design intent and site constraints, leading to more constructive and relevant findings.

Respond promptly to findings. The Designer’s Response should be prepared and submitted within two weeks of receiving the audit report. Delays in responding delay the technical approval and, ultimately, the start of works.

Do not treat the RSA as a formality. The audit process exists to protect road users and, ultimately, to protect you. An RSA that identifies a genuine safety issue is doing its job. Address the findings, improve the design, and move on.

How We Can Help

Our highways team manages the full RSA process as part of our highway design and Section 278 services. We coordinate audit appointments, prepare the design submissions, manage the Designer’s Response process, and liaise with the highway authority throughout. If you need support with an RSA — or if you are unsure whether one is required for your scheme — get in touch.