By Gordon Dickson, Fort Worth Star-Telegram; April 26, 2019
FORT WORTH
Some tanker cars involved in a fiery train derailment Wednesday in south Fort Worth were older model rail cars that are considered less safe for transporting flammable liquids than newer models, federal officials say.
The older tanker cars, known as DOT-111s, are being phased out and will no longer be allowed on U.S. railroads by 2023, according to federal regulations. The DOT-111s are being replaced by DOT-117 tanker cars, which feature thicker protective shells, head shields (to reduce collision impact) and an additional thermal protective layer of fiber.