For safety reasons, passengers with disabilities or reduced mobility are not allowed to occupy seats where their presence could:
- interfere with the crew's work;
- obstruct access to emergency equipment; or
- hinder the emergency evacuation of the aircraft.
The vast majority of airlines place persons with disabilities or reduced mobility near the window when they are unaccompanied.
Under no circumstances may passengers with disabilities or reduced mobility be placed near emergency exits. Passengers placed near the emergency exits must be able to support the cabin crew during a possible evacuation. This prohibition applies to all persons who are not able to operate the emergency exit: e.g. small children, mentally handicapped persons, elderly persons, persons with a large body, persons with a broken hand or leg, pregnant women, etc...
Even paying an extra fee in advance to reserve a place near the emergency exits will not get around these mandatory rules.