Road Restraint Risk Assessment Process (RRRAP)

The design standard has two parts that must be used together:

• The written Standard CD 377 'Requirements for road restraint systems', which contains mandatory requirements
• The 'Road Restraint Risk Assessment Process (RRRAP)', which enables the designer for each site/scheme to establish the need for a vehicle restraint system and, where required, its minimum performance requirements

The RRRAP provides the designer with a tool to assist in the provision of a risk reduction design for hazards that are sited adjacent to the carriageway. It also provides a record of the minimum vehicle restraint provision which the designer will then optimise through the design process. The RRRAP tool can be found here.

It applies site specific data to each hazard, allowing both the risk of impact and the likelihood of occupant injury to be assessed. Multiple factors can be incorporated where they influence the potential injury risk to occupants of an errant vehicle. Factors considered include offset from the running lane, topography of the ground in advance of the hazard, the aggressiveness of the hazard itself and other factors such as accident rate, traffic volume, vehicle type and any effects on third parties.

The formulae within the RRRAP reproduce research findings which reflect risk factors found in a number of research reports undertaken in the UK and Worldwide. These are summarised in the TRL report “The travel of errant vehicles after leaving the carriageway”. The outputs of RRRAP were benchmarked against IRRRS and TD19/85 and have been developed through the continuous improvement process leading to the release of RRRAP v3. 

The RRRAP outputs provide a good basis for hazard mitigation solutions whether that is removal of the hazard, installation of passively safe furniture or protection with vehicle restraint systems. 

RRRAP account application process – For all schemes except those on the Welsh motorway and trunk road network

Each organisation will request a username and password for their organisation by means of a nominated super-user who will administer access to their allocation of record slots to other designers within their organisation. All slots / records are accessible only to the organisation to which they are allocated.

The organisation's super-user will need to demonstrate current and future scheme records or justify the issue of an account for other reasons (education, training or research purposes).

The number of slots allocated to each organisation will be made based on workload / expected users.

Super-users will be notified of their account details by email, together with the location of the login page. Super-users can create accounts for other users within their organisation from the account administration section within the RRRAP.

Please note: RRRAP is not a storage system, records should be exported and backed up on a frequent basis. It is required that once the design been concluded, reports are outputted and stored in the design file for the project. The record should then be removed by exporting it to free up record slots. Exported records can be imported back into RRRAP at a later date if required.

RRRAP account application requests

Send email request to: RRRAP@nationalhighways.co.uk

State organisation registration request in the subject line.

The email should contain:

• organisation name / division / address / contact details
• an organisational or corporate logo in gif format (100kB max) for the printing of reports
• statement of reason for RRRAP access request
• name and contact details for nominated super-user (first point of contact for organisations users i.e. new accounts / password resets / technical queries)
• name and contact details for deputy (in case of illness) for switching super-user role on request
• estimated number of schemes in next year
• estimated number of users expected

RRRAP account application process – for schemes on the Welsh motorway and trunk road network

Where required in accordance with Welsh Government PAG 119/23, the RRRAPfW assessment should be undertaken using the Wales organisation area within WebRRRAP.

To access the Welsh Government area of WebRRRAP the user should send an email request to: RRRAP@gov.wales with the following details:

• User name
• Organisation name
• Email address
• Contact number
• Regional area (SWTRA / NMWTRA)

Note: RRRAPfW is not a storage system; records should be downloaded / backed up on a frequent basis. It's required that once the design has been completed the record is removed (downloaded by csv file) to free-up record slots.

For any RRRAPfW / risk assessment to be completed, all record declarations need to be completed and signed off. Once the declaration is signed and the entry is final the output csv file is to be submitted to RRRAP@gov.wales where the record will be retained on the Welsh Government asset management system for future needs.