By CBS3 Staff

PHILADELPHIA (CBS) — It’s something you hope never happens, but you have to be prepared just in case. Emergency crews in Montgomery County spent Sunday morning preparing for the unthinkable.

A simulated terror attack on SEPTA’s Rail Lines was held on Sunday morning with emergency crews from Lansdale and surrounding towns trained for if the real thing ever happened.

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“How much work do we need?” SEPTA Fire Marshal John Townsend said. “How many vehicles do we have to have? Is our mass casualty plan good enough?”

The drill is that a box truck carrying explosives intentionally crashed into a SEPTA train. The simulation included responding to the scene and getting victims to safety.

Crews were also graded on their response.

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The federal government requires SEPTA to do this training once a year. The idea is that response crews will be able to better respond if a real call comes in.

That call did come six years ago after the deadly Amtrak train derailment on May 12, 2015.

Eight people were killed and more than 200 were injured when a Northeast Regional train derailed in Port Richmond.

They say seeing what could happen in real life is even more of a reason to prepare.

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“Preparedness is prevention,” Fairmount Fire Department Assistance Chief R.J. Snyder said. “Every chance we get to train, we do.”