How science can help cities prepare for attacks on metro systems

Recent events in St Petersburg remind us of the challenges faced by underground transport systems

Tokyo, Moscow, Madrid, London, Brussels, and now St Petersburg. These major cities have all suffered attacks on their metro systems. The most recent events in St Petersburg, where a metro bombing killed at least 14 people, remind us of the challenges faced by underground transport systems in keeping people safe during an emergency. This is where engineering and psychology research can come in useful, helping to optimise evacuation procedures using insight into how people behave.

To start with, there are several key ways that evacuating an underground system differs from evacuating a building. Underground environments are often unfamiliar