Trinity Industries manufactures guardrails used on highways in nearly every U.S. state. But in the past nine months, Nevada, Missouri, and Massachusetts have all banned the company's products, claiming that the company's ET-Plus guardrails are unsafe due to a money-saving design change that was made after the rails were crash-tested and approved. That design change is said to save Trinity Industries a mere $2 per rail—but it could be causing the rails to impale cars in head-on collisions.

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After the rails were approved, Trinity tweaked the design, narrowing a steel channel behind the guardrail cap from five inches to four. Officials say that instead of the guardrail crumpling and folding out of the way in a head-on collision, the mechanism can jam, turning the guardrail into a giant skewer. Lawsuits claim that four deaths and numerous injuries are the result of the change.

The company never disclosed the change to the Federal Highway Administration. And internal communications obtained by The New York Times show that agency engineers felt the alteration to the design made the guardrails unsafe. One email from a senior engineer stated it was "hard to ignore the fatal results." But while FHWA engineers drafted a letter seeking additional testing from Trinity, that letter was never sent.

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In January, Nevada's DOT prohibited purchase of ET-Plus guardrails, citing Trinity's undisclosed design changes. Massachusetts and Missouri have since done the same. While the FHWA is still reimbursing states for purchase of the guardrails, it has asked state transportation departments to submit data on crashes involving ET-Plus guardrails. And news channels have picked up on the brewing controversy:

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As it stands, three states have already banned the further installation of Trinity guardrails this year. With increasing scrutiny on the issue, more could follow. It's unclear how many miles of U.S. highway have these rails installed, or what states will do about them, but it's troubling. And potentially dangerous.

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