Standards Development

Scope

This PAS specifies requirements for operational safety cases and the supporting safety management system for automated vehicle tests and trials in the UK to demonstrate that the operation of automated vehicles can be undertaken safely and securely within the defined operating environment. It applies where the vehicle and its surroundings are being continuously monitored by a safety driver or safety operator within the vehicle with the capability to intervene in the performance of the driving task immediately.

NOTE 1 This PAS does not apply to testing or trialling using a remote safety operator. However, it does apply if there is a remote operator who is supported by a safety driver or other form of on-board safety operator who is able to intervene in the event of an unsafe input from the ADS and/or the remote operator.

NOTE 2   While the term ADS (automated driving system) is used throughout, it should be noted that the scope of this PAS applies to systems under development and trial that require continuous supervision. As such, references to an ADS within this PAS apply to supervised systems, as opposed to an ADS that is ready to provide automated driving without supervision.

This PAS covers the development and maintenance of an operational safety case to demonstrate that the risks to all affected parties throughout the operation of automated vehicles are reduced to be as low as reasonably practicable (ALARP) and that the test or trial does not present any unreasonable risks. This includes operational risk assessments, training of personnel, safety monitoring, compliance and permissions granted. It is applicable to all roads and public spaces and to tests or trials of systems that aim to automate both the longitudinal and lateral vehicle control aspects of the dynamic driving task.

NOTE 3 This PAS primarily supports applications on roads and in public spaces; however, it can be used as guidance for testing or trialling in controlled environments such as proving grounds, roads that don’t have public access, or for off-highway applications (e.g. farming, quarrying, defence or warehouse applications), in the absence of other relevant and applicable standards.

This PAS includes assurance of overrides for the automated driving system (ADS), to enable safety drivers or operators to intervene in the driving task appropriately when required, including in emergency scenarios and proactive takeovers, such that they are able to be relied upon as a safety mitigation.

NOTE 4  Examples of overrides might include an emergency cut-out switch that prevents the ADS providing further control inputs to the vehicle, or the ability to provide direct control inputs (e.g. via a steering wheel) that override control inputs from the ADS.

This PAS does not specify requirements for the system safety of the vehicle, such as functional safety, safety of the intended functionality (SOTIF) or cybersecurity assessments, other than for the assurance of the robustness and appropriateness of control interfaces for overrides. However, it does require that key system safety findings are taken into account where they are relevant to the operational safety case, such as where there are flaws identified in the system behaviour that it would be appropriate for safety operators to be aware of. This PAS does not include the safety case requirements for the testing of a connected vehicle that is not also automated.

This PAS is intended for use by trialling organizations, including private developers, original equipment manufacturers (OEMs) and operators, who are developing safety cases for automated vehicle testing or trials.

This PAS does not specify requirements for the passive safety of the physical vehicle, but does include requirements relating to the operational safety implications of any modifications to the base vehicle (e.g. after type approval), such as the fitment of hardware in locations that might inhibit visibility, inhibit egress or be impacted as a result of an occupant's movement.

This PAS might be of interest to any organization that utilizes or develops an ADS. It might also be of use to road authorities, local authorities, test beds, service operators, vehicle agencies and insurers.