Safe System audit (SSA) procedures for transport projects

The Safe System audit guidelines provides guidance for undertaking Safe System audits for transport projects in New Zealand.

Safe System auditing procedures for transport projects

It replaces the existing road safety audit procedures for projects guideline interim release May 2013.

This guidance brings together key elements of both the Safe System assessment framework and road safety audit procedures to provide a comprehensive transport project audit that assesses both the Safe System alignment, and the risk ranking of road safety concerns at the different stage of the project in the development cycle.

This guide also provides clients, project managers and project sponsors with information on current practice in the management and delivery of the Safe System audit process.

This guide clarifies the roles, responsibilities and relationships of the client team, project sponsor, project manager, audit team and audit team leader.

Note: This page is guidance only. Please consult the full guide available via the link above.

Safe System audit (SSA) definition

A Safe System audit is a formal, robust technical assessment of transport safety risks associated with transport improvement and renewal projects that are completed by independent and qualified audit teams, they consider the safety of all people and are completed by applying Safe System principles while seeking to ensure that the transport network will operate as safely as practicable by eliminating fatal and serious injury crash potential.

A Safe System audit is intended to support the delivery a safe road system and is not a review of compliance with standards.


Putting people and their safety at the centre of our transport planning and project development is critical to achieve our Vision Zero aspirations and the Safe System audit guide supports this.

Essential elements

A Safe System audit must:

  • focus on the safety aspects of the project
  • be carried out by people who are independent of the client, designer or contractor
  • be carried out by people with appropriate experience and training, and who understand the Safe System approach
  • be a formal documented process
  • consider all people who access the transport network
  • include a formal documented response from the client.

However, a Safe System audit is not intended to be:

  • a substitute for a quality control review, a design review or a peer review
  • a judgement of the quality of a project (as the project will likely have other components)
  • a compliance check with standards, guidelines or drawings and specifications (a separate review is required for this purpose noting that compliance with standards or other documents does not necessarily result in a safe system)
  • a redesign of a project
  • an informal check, inspection or consultation
  • a means of ranking or comparing one project or option over another (although it may form part of the decision process).

While engineering design standards and guidelines can provide a sound starting point from which a good design can evolve, their application alone does not necessarily result in the safest road environment. Safe System audits provide a further means of checking a projects alignment to road safety outcomes.

When to undertake a Safe System audit (SSA)

A Safe System audit should be undertaken at project milestones such as:

  • concept stage (part of a business case)
  • scheme or preliminary design stage (part of pre-implementation)
  • detailed design stage (pre-implementation or implementation)
  • pre-opening or post-construction stage (implementation or post-implementation).

These milestones align approximately with the development cycle of a project. These stages should not be seen as rigid, as all projects are not the same and smaller projects will not always follow all the development stages. The stages of a Safe System audit should match the project’s complexity and actual development stages. However, the earlier an audit is undertaken, the easier and less expensive it is to make changes.

Conducting a Safe System audit only at the post-construction stage should be avoided, as often it is too late to make significant improvements if required.

It is recommended that each road controlling authority embed the requirements for a  Safe System auditing procedures for transport projects in appropriate policy documents, including but not limited to asset plans, safety management systems and development codes. As a minimum it is recommended that a safe system audit be undertaken at the design stage for all works within a public space.

For requirements specific to a particular road controlling authority, refer to the policy of that authority.

Other safety review/audit tools

There are many other safety review and audit tools that are used throughout the project life cycle.

Temporary traffic management (TTM) audit procedures

Temporary traffic management safety audits must be carried out in accordance with Waka Kotahi Traffic control devices: part 8 COPTTM, section A8 – temporary traffic management safety audit procedures.

It is recommended that auditing of worksites be carried out by both the road controlling authority and any party who has activity completed for them on the roads. This is to provide assurance that good traffic management is being achieved and, if not, to identify problems that need to be remedied.

The road controlling authority monitors documentation and activities to ensure continuing effectiveness and uniformity of TTM.

People using these procedures must hold a current STMS or STMS-NP certification (refer to subsection A5.8 Site traffic management supervisor) to the level of the TTM for which they are auditing.

Land use development reviews/audits

Land use developments can have an impact on the roads they connect with or another road some distance away. Developments of any magnitude have their own car parks, driveways and footpaths. Thus, they have traffic interactions in the same way as do roads.

Private land-use developments often involve the design and provision of proposed roads or modification of existing roads. While in such instances the developer is effectively the client for the safe system audit process, involvement of delegates from the road transport authority (for example Safe System engineer or consent specialist) is recommended so that the audit findings are responded to from the perspective of the ultimate asset owner.

Network safety reviews

Network safety review involves the principles of Safe System auditing and crash investigation. It is conducted by a Safe System and/or road safety professional.

It is an assessment of proposed or existing roads and road related areas from the perspective of all road users with the intention of identifying Safe System concerns and areas of risk that could lead to or have led to death and serious injuries.

Cycle safety audit and network functionality review (SANF)

The cycle network guide suggests in addition to the Safe System audit that a ‘peer review’ is a review of a concept, scheme or detailed design undertaken by a suitably qualified and experienced person independent of the design team. It is good practice to include peer reviews during the design process, and they are often required by road controlling authorities.

In lieu of any available structured process or report template, the five main aspects that a network of cycle routes should provide could be used as a basis for the review:

  • safety
  • comfort
  • directness
  • coherence
  • attractiveness.

The SANF is an example of a peer review process that considers operational, functional and safety matters. It was developed in Christchurch for cycle projects.

Non-motorised user review procedures (NMUs)

This is a systematic process applied to new roading projects by which the design team identifies and documents existing and potential issues affecting  NMUs, sets project objectives to improve conditions for NMUs, audits designs and construction to assess how well the objectives have been achieved, and documents the design decisions that have been made.

The NMU review considers how the roading project recognises and balances the needs of all the existing and forecast groups of users. In this way the NMU review is not constrained to simply checking that NMU facilities are adequate and that the design accommodates NMUs but also examines how opportunities for NMUs can be maximised and enhanced.

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