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From their website:
http://www.rtd-denver.com/Archive/Ho...mfortably.html

Riding Tips...
  • Please don�t take up more than one seat if the bus or train is crowded.
  • Let passengers exiting the bus or train get off before you get on.
  • Stay in your seat while the vehicle is moving. If no seats are available, move to the back of the bus or light rail car and hold onto the poles or straps provided for your safety.
  • Seats near the front of the bus and each light rail car are priority seating for senior citizens and disabled riders. Please be courteous and give them your seat if you see them standing.
  • Do not lean against the doors inside a bus or train.
  • Do not leave any valuables in stations or on buses or trains.
  • Keep aisles clear of parcels and packages. Any items you bring on board should be small enough to fit on your lap or at your feet in front of you. Skis or other sports equipment should be in protective carrying bags.
  • Keep your head and hands inside the bus at all times.
...and Rules of the Road
  • Please don�t engage in idle conversation with the driver, as this can distract from safe driving practices and inconvenience other passengers.
  • Smoking on buses and light rail trains is prohibited.
  • Shirt and shoes are required.
  • Express and Regional bus passengers may bring food and drink onto the bus, as long as drinks are in a sealed cup with a small opening in the lid.
  • Radios/boomboxes may be played only if headphones or ear pieces are used and the volume is not offensive to other passengers.
  • Babies are welcome if held on your lap. Keep strollers folded up and out of the way of other passengers. Hold small children securely during your trip.
  • Guide, signal and service dogs are allow to ride for free with passengers who have visual, hearing or mobility impairments. All other animals are allowed only if they are kept in a cage or container.
  • No weapons, firearms, or dangerous or flammable materials are allowed.
  • No littering.
  • No panhandling, begging, sales or soliciting for donations on buses or light rail trains.
  • No vandalism, graffiti or etching on windows. These are considered crimes and are punishable by a fine or jail sentence.
  • Be kind to other passengers and your bus driver. Speaking on cell phones disturbs those around you and may distract the bus driver.