Tank Car Safety Act of 2014 - Directs the Secretary of Transportation (DOT) to revise federal regulations regarding DOT-111 tank cars used to move flammable liquids to: (1) improve tank car design standards for new cars to include an outer steel jacket around it and thermal protection, full-height head shields, and high-flow capacity pressure relief valves; and (2) require additional safety upgrades to tank cars built after October 2011 by including installation of such valves and design modifications to prevent bottom outlets from opening in case of accident.
Directs the Secretary to submit to Congress a plan to phase out older-model DOT-111 tank cars that are not retrofitted to meet the new federal requirements.