GG104 'Requirements for Safety Risk Assessment' is part of the Design Manual for Roads and Bridges (DMRB), setting out the framework National Highways requires for managing safety risk to customers, workers and other parties across all activities affecting the strategic road network. It replaced the former GD 04/12 and IAN 191/16 documents and applies to any scheme, maintenance activity or third-party works that could have a direct or indirect impact on road safety.
GG104 requires the Safety Risk Assessment (SRA) process to be documented through a series of defined steps, from initial hazard identification through to formal sign-off, ensuring that safety risk is properly considered, evidenced and governed at every stage of a scheme's development.
When GG104 applies
GG104 applies to activities on motorways and all-purpose trunk roads managed by National Highways, and to third parties planning works on or adjacent to the strategic road network (SRN). It is used throughout the scheme lifecycle - from early options assessment through detailed design, construction and into operation - wherever a change could affect the safety of customers, the workforce, or other road users. Where a scheme also affects the local road network, the SRA sits alongside other safety processes such as Road Safety Audit and, where restraint systems are involved, the RRRAP methodology under CD 377.
What the process
- Identification and classification of hazards arising from the scheme, activity or change
- Assessment of the likelihood and severity of harm to customers, the workforce and other affected parties
- Evaluation of existing controls and identification of further mitigation measures where required
- Categorisation of the scheme (Type A, B or C) to determine the level of rigour and governance needed
- Preparation of a Safety Report, developed and updated as the design progresses through each stage
- Formal review, approval and sign-off in line with the relevant safety governance procedures
- Maintaining a clear, auditable record of decisions to demonstrate compliance with legal and organisational safety obligations
Our experience
MERAKI has direct experience delivering GG104 Safety Risk Assessments for major schemes affecting the strategic road network, including work supporting the safety risk assessment for new travel hub and active travel infrastructure crossing the motorway network. Our engineers are experienced in structuring the SRA process to meet the requirements of GG104, engaging effectively with scheme stakeholders and safety governance teams, and producing clear, well-evidenced Safety Reports that support timely scheme approval.
