Originally Posted by
mahasamatman
OP has posted in the LGW thread as well, so that must be the one.
In that case, look into the Montreal Convention, and, naturally, WestJet's International Tariff. Plus, if the departure is from LGW, European regulation applies, which offers a lot more protection than Canadian law:
http://europa.eu/youreurope/citizens/travel/passenger-rights/air/index_en.htm