Towards A Complete Description of The Safe System

The Safe System has been described in a range of strategies and other publications. Consistently, these describe a number of factors, typically infrastructure, speed, people and vehicles, to indicate that a safe or safer system will be achieved by actions across all of these. This paper examines an alternative model in which these “pillars” are not inputs to achieve safety but are outputs of the interactions within the system. Speed, vehicle and environment describe the system state for each individual. Some implications of describing system risk as a function of these three variables are also discussed.