In Canada, there is a requirement that
...air operators establish procedures to ensure that seats located at emergency exits are not occupied by passengers whose presence in those seats could adversely affect the safety of passengers or crew members during an emergency evacuation.
Passengers seated at exits:
* must be physically capable of using the exit;
* must be capable of understanding the printed and spoken emergency instructions;
* must be able to visually determine if the exit is safe to open;
* must have sufficient mobility, strength and dexterity to reach, operate and stow (or otherwise dispose of) the emergency exit;
* must be able to receive aural information from the crew and to orally communicate that information to other passengers;
* must be of a minimum age (as established by the air operator) to ensure that he/she has the physical, cognitive and sensory capacity to operate an emergency exit;
* must not be responsible for another person as this can hinder the opening of the emergency exit; and
* must not have a condition which might cause them harm by opening the exit.
Passenger Seating Requirements
[ 18 August 2001: Message edited by: CD ]