A previous ShortCodes module (1C) included information about use groups and occupancy classifications, which designate the use of the building, room, or area.  In order to interpret the code requirements, we must determine which use groups or occupancy classifications apply, AND what the occupant load is.  For example, doors are required to swing in the direction of egress when serving an area with 50 occupants or more.  We need to calculate the occupant load so we will know whether the door is required to be outswinging.

The occupant load is determined by a calculation using the area of the building, room, or space, and an occupant load factor.  The occupant load factors vary depending on the occupancy type – a classroom has an occupant load factor of 20 net square feet per person, and the stack area of a library has an occupant load factor of 100 gross square feet per person.  This accounts for the relatively lower number of occupants in the library, and the square footage used for bookshelves and other furniture or equipment.

Based on the area in square feet divided by the occupant load factor (X square feet per person), you can determine the occupant load of the space.  To learn more about calculating the occupant load, read this Decoded article and then proceed to the review questions below.


Review Questions

1. Which of the following formulas represents the calculation for determining the occupant load?

  1. Area x Occupant Load Factor
  2. Area / Occupant Load Factor
  3. Volume x Occupant Load Factor
  4. Egress Width / Occupant Load Factor

2. What is the calculated occupant load of a classroom with a net floor area of 960 square feet?

  1. 26 people
  2. 32 people
  3. 48 people
  4. 50 people

3. Which occupant load factor would be used for the dining areas of a large restaurant?

  1. 5 square feet per person
  2. 7 square feet per person
  3. 15 square feet per person
  4. 20 square feet per person

Answers: 1 – B, 2 – C, 3 – C