Conclusions

• A process-based approach has the potential to become a/the mainstream approach to safety assurance as regards human aspects of systems (and possibly for all aspects).

• Design principles complement process measures, but are dependent upon process capability for their achievement.

• Process metrics can (rightly) relieve safety culture of a role in safety assurance.

• The possibility of using process metrics in the context of Regulation is intriguing and appears to be under consideration in a number of places.

Recommendations

• To pilot ISO PAS 'HS', in conjunction with ISO CD 15288, for an explicit role in safety assurance.

• To progress the work started by [Benediktsson et al 2001] on the mapping of process models (especially ISO 12207) and IEC 61508:1998.