Claims for whiplash type injuries in most motorised countries cost more than all other injury claims put together. In Britain changes in the legal process within the last 10 years have led to a 50% increase in such claims. When followed up in detail a proportion of such claims have been shown to be invalid. The aim of this research is to develop an analytical technique for assessing the severity (delta‐v, average acceleration and other parameters) of an impact to a car involved in a low speed rear end collision. That information, when combined with other factors (i.e. gender, occupant position and posture, seat performance and published data on injury incidence) allow the injury risk to be assessed for each given case. The aim is to provide a filter which will identify those cases where the crash severity is so low that the chances of a whiplash injury are remote. This paper presents a new way to combine the state of the art in whiplash research into one system using damage severity estimation, seat performance information and published modifier data for factors which influence the likelihood of whiplash in rear end collisions.