Take care on the tracks!
1. If you drop your bag, contact an MTA worker - he or she will help you retrieve it at a "safe" time.
2. If for some reason you find yourself in the path of an approaching train, do not try to run or get out of the track. Rather, lie face down as flat as you can at the center of the rails (ie, so that the train passes OVER you.) Disgusting, rat-infested, and murky - but it will keep you alive.