Controls Today’s railroad cars incorporate many safety features. Ladders have rungs
that prevent feet from sliding off. There are grab bars at climbing transition points and
slip-resistant walkways and handrails. Thermally insulated tank cars prevent heat buildup
and explosions from fires in adjacent cars. Cars carrying hazardous materials have inter-
locking couplings. Locomotives have dead-man controls to prevent runaway trains should
an engineer become incapacitated. Cars containing hazardous materials have placards indi-
cating contents and type of hazard. Automatic sensors placed strategically along main lines
detect overheated bearings.
Based on traffic at crossings, more and more grade crossings are being protected by barrier gates and signals. Sensors that detect the speed of a train activate some gates and ensure adequate lead time for gates to close. Major highways avoid grade crossings with underpasses and bridges. Some cities are diverting main line rail traffic from the inner cities where dangerous traffic conflicts exist.