On my recent visits to Paris, I noticed that the Metro was more crowded than ever.But it seemed that Parisians were relatively civil compared to subway riders in NYC, or even London. So, I was a bit surprised to see a new “rule book” for travelers published by RATP, the company that runs the Metro system.

The handbook, titled “An Etiquette manual for the Modern Traveler”, was created based on complaints from Metro riders. passengers submitted thousands of suggestions, which were pared down to 12 rules for riders.

Anyone who has traveled the Metro during warm weather months will appreciate rule #3: “On really hot days, even an emperor penguin needs to keep his arms close to his body, so grab the bottom of the post and not the top.”

The rule book, which is available on line here, is a follow-up to a poster campaign launched this summer by RAPT aimed at schooling Metro riders on civil behavior.