The Alberta Building Code does not provide a definition for what constitutes a bedroom but it states minimum safety measures required when a room is intended to be used for sleeping. They suggest for a room to be considered a bedroom; it must provide one of the following:
a minimum level of safety in the form of an egress window with an unobstructed opening, not less than 0.35 m2 and no dimension less than 380 mm OR
a door leading directly to the outdoors OR
the suite is fully sprinklered
In addition to the egress requirements, consideration should also be given to the placement of smoke alarms and carbon monoxide alarms.
A common standard used by most real estate agents is that a bedroom needs a window/egress and a closet. However that isn't the legal description.
An important consideration when buying or selling a home and deciding if a room should be considered a bedroom or not is... what will your buyer consider a bedroom? Arguing with your potential buyer about a technicality on the definition doesn't usually result in an accepted offer.