In American/Canadian parlance "gas" as discussing flammable fuel almost always means "gasoline" with exceptions like "gas main" or "gas canister" where it refer

In American/Canadian parlance "gas" as discussing flammable fuel almost always means "gasoline" with exceptions like "gas main" or "gas canister" where it refers to "natural gas" (methane) or in the case of the canister, possibly propane, but usually people say "propane canister" or "propane tank" to be specific.