Before participating in a sporting event, it is always a good idea to find out what the rules are! Here are some useful links for your preparation:
Competition rules - Triathlon Quebec: (french only) The Triathlon Quebec (TQ) federation is THE reference for triathlon rules in Quebec. TQ definitely has answers to all your questions! There are also online videos and training modules for those who would like to get involved as an official. Why not?
Competition Rules - World Triathlon: The international triathlon federation writes the rules of competition at the world level. The TQ rules are based on the World Triathlon rules, but with some adaptations for the age group component.