Cathy from Pittsburgh on 9/23/2018 5:43:59 PM:
Call me old-fashioned, but if it is something you are instructed not to carry on a train, you should not carry it on the train. In this day and age law enforcement etc is alert to bad actors and you could be mistaken for one if you have a gas cannister in your bag. Perhaps you don't watch the news. There are people who are into setting off bombs in train stations. Just drop in an REI at your destination and pick one up there.