Ian Johnston, the Head of Engineering at D/Gauge, is an expert in the field of clearance assessment. D/Gauge has been at the forefront of extensive research into the impact of track transitions on vehicle movement and the resultant clearance envelop. This ground-breaking work has led to the development of innovative approaches that provide a comprehensive understanding of these effects. In his upcoming talk, Ian will deliver an insightful presentation that will explore the historical and current transitional methods employed in clearance assessment. Attendees can expect a comprehensive review of the underlying rationale behind past practices, accompanied by a detailed analysis of the advantages and disadvantages associated with the diverse range of methods available today.