Field trials under way in Arizona promise eradication of accidents between emergency vehicles at intersections – as part of a national focus on ‘intelligent signal’ infrastructure. Collisions between police cars, ambulances and fire crews as they reach intersections at the same time, with equal priority given by all signals set on red, are as serious as they sound absurd. For emergency teams and those in need of their help, the consequences are dire. The solution could come from application of connected veh