Nope, the size of beds does not equate to room capacity. You can have six sleeping spots but fire codes limit the room capacity to 5. So, they can only advertise the rated room capacity thus "sleeps 5"./QUOTE]
Okay, I have a lil confession. I"m a lil obsessive. Actually, I think most Disney lovers are. Several years ago when my youngest of 4 was 3, we did not fit into a room for 5 anymore. I looked at square footage of rooms. The number of people to the square footage didn't match up at all the resorts. As I am sure many have been told by the reservation cast members, the number of people in a room is determined by fire code. SOOOOOooooo, I called the county fire chief and inquired what the criteria was for the Disney properties for number of people in a room. He said it was determined by Disney and reported to the fire department how many people are in a specific room in the specific resorts. This way they would know the maximum number of guests. So, yes it is fire code, however that code is based on what Disney sets.
Occupancy isn't based on square footage in hotel rooms. It is based on the number of people in the room. Square footage is the deciding factor in assembly occupancies like theaters and ballrooms, and such. I'm sure you have seen signs in places like that which say this space is limited to XX many occupants. Hotel rooms they need to calculate the number of feet coming out of the room in a fire, how many rooms and the width of the corridor and stairs. If there are too many bodies walking/running out of the room, and not enough space in the corridor/stairwell, people get trapped. So it's not the space in the room, it's the space in the corridor and stairwell.
Read about the Triangle Shirtwaist Factory fire in the early 1900's. It kind of explains why the occupancy limits were determined as they were.
Some building owners/states/counties/parishes/cities use the National Fire Protection Association Code 101, the Life Safety Code. Others use different building codes, like the UBC (Uniform Building Code), which are very similar.