What do pressure tank cars typically transport?

Pressure tank cars are specifically designed to transport substances that are kept under high pressure. This construction is necessary for handling gases that remain in a liquid state at elevated pressures, and it also allows for the safe transit of toxic or hazardous materials that could present risks in their gaseous form.

The correct focus on propane, ammonia, and chlorine aligns with the typical contents of pressure tank cars. Propane and ammonia are common industrial gases that can pose significant safety risks if not handled correctly. Chlorine is another important substance used in various industries, including disinfection and water treatment but is highly corrosive and toxic, making its secure transport essential.

The other options refer to materials that do not necessitate the specialized design and pressure handling capabilities of these cars. Flammable liquids and miscellaneous solids may be transported in different types of tank cars more suited to those categories. Likewise, food products and agricultural chemicals often use tank cars designed for non-hazardous cargo, while the transport of flammable gases and corrosive materials requires specific containment and handling measures that align more closely with pressure tank car specifications.