Flight Attendants

I'm not sure the general public has a real appreciation for the role of flight attendants as essential crew members.  They are our eyes and ears in the cabin, and they are integral to the safe operation of the aircraft, especially in emergency situations. 

CAR 705.104 Flight Attendant Requirements

(1) the basics:

(a) 1 - 40 pax ... 1 attendant

(b) 41 - 80 pax ... 2 attendants

(c) 81+ pax... 1 attendant for every unit of 40 pax or portion thereof

Of course, there are exceptions

(2) you may need more if required to cover all duties in the event of an emergency, or if required by the company operations manual

(3) you may use less if authorized on the air operator certificate

(4) if there is more than 1 deck (i.e. B747 or A380), (1) and (2) apply to each deck