The transportation of hazardous cargoes by truck, notably flammable liquids such as gasoline and home heating oil, pose analytical and policy challenges. These vehicles are generally prohibited in tunnels, prompting concern about their presence on alternate routes.
The analytical challenge is measuring the presence of hazardous cargoes on roadways. Using technical counting means, these vehicles are indistinguishable from trucks of similar size and configuration. Hazardous cargo vehicles bearing required red safety placards must be observed visually.
This study presents summaries of hazardous cargo vehicle counts undertaken in recent studies. These data are presented in tables and on a core area map. Types of hazardous cargo vehicles are described and key travel corridors and flow patterns are illustrated.