Factual error: Filbert is in the southwest corner of PA. It is very far out of the way of Harrisburg and completely off the route from Philadelphia to Harrisburg.
Factual error: There are no tracks, stations or train routes in Filbert, PA.
Factual error: The cars the train is pulling for the Philadelphia to Harrisburg route are not ones that represent any passenger cars used for the Amtrak or Keystone routes. They are SEPTA cars on an undisclosed route, other than the Harrisburg line.
Chosen answer: If it would/could wear off would be debatable. As far as sending troops in wearing gas masks: The masks are simply filters that block molecules of certain sizes. If the neurotoxin molecular structure was small enough, it could pass through the filters. And then there is, if you really wanted to die, you will find a way regardless of the situation.
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