The safety advisory re-emphasizes concerns with the survivability of DOT-111 tank cars and encourages tank car owners and shippers of flammable liquids to voluntarily upgrade their tank car fleets to the DOT-117 specification tank car, the newest and safest available tank car design authorized for flammable liquid service. The advisory also urges rail carriers to consider the risks inherent in the continued use of DOT-111 tank cars in flammable liquid service, and to take actions that could reduce the risks of hazardous material transportation by rail.