This is a chapter from Safety and Security in Transit Environments: An Interdisciplinary Approach edited by Vania Ceccato and Andrew Newton. This chapter is available open access under a CC BY license. As other chapters in Safety and Security in Transit Environments assert, crimes such as pickpocketing can concentrate near bus stops, and crowding and congestion is a factor that heightens this risk. But to target interventions effectively, it is useful to determine what local-level interactions characterise this crowding behaviour. This paper aims to provide a first step to using data collected from laboratory experiments to address questions from crime and transport research. The experiment considered differences in interpersonal distances to further analyse crowding behaviour to attain further insight that could narrow the focus of possible interventions. Audio warnings are examined as a possible solution, and findings show that crowding peaks when passengers board the bus, and audio messages may be one approach for addressing this. To conclude, implications of identifying boarding as a problem area, and the effectiveness of warning messages as a situational crime prevention tool are discussed. This work was published by Saint Philip Street Press pursuant to a Creative Commons license permitting commercial use. All rights not granted by the work's license are retained by the author or authors.