This paper describes a method for determining whether a person will make a journey or not, by breaking down a journey into a series of potential barriers, all of which must be successfully negotiated before the journey will be made. Reduced mobility (a mobility handicap) is seen in two different ways. As a symptom of disability, which can be removed through making the existing transport system physically accessible, or secondly, as a symptom of a transport planning system and an inter sectoral resource allocation procedure which is out of tune with the needs of a major section of the population. To remove mobility handicap in this second context requires the redefinition of the role of public transport and a much more rigorous approach to the design of services. Each of these approaches uses the concept of a 'chain' with individual links. There are, however, radical differences between the two approaches. The second approach incorporates the first, while the physical access model too often excludes proper consideration of all potential passengers. The most powerful use of the chain concept is in understanding the process of making a journey and identifying all elements requiring design attention. Used in this way the chain concept clearly identifies the dynamic nature of mobility handicap.
Abstract