If a space has fixed obstructions such as columns and fixtures, which occupant load measure is most appropriate?

If a space has fixed obstructions such as columns and fixtures, which occupant load measure is most appropriate?

• A. Gross occupant load factor
• B. Net occupant load factor
• C. Both are equally valid
• D. Neither is used

Answer: (B)

When fixed objects are present, base occupancy on usable space rather than total space. Occupant load factor tells you how many square feet per person are allowed, and you determine the number of occupants by dividing the usable floor area (excluding fixed obstructions like columns and fixtures) by that factor. This net approach reflects reality: the area actually available for people to stand and move around is smaller, so the maximum safe occupancy is lower. Using the gross area would overstate available space and could lead to unsafe egress conditions. The other ideas aren’t appropriate here because fixed obstructions reduce usable area, and you still need a method that accounts for that.

When fixed objects are present, base occupancy on usable space rather than total space. Occupant load factor tells you how many square feet per person are allowed, and you determine the number of occupants by dividing the usable floor area (excluding fixed obstructions like columns and fixtures) by that factor. This net approach reflects reality: the area actually available for people to stand and move around is smaller, so the maximum safe occupancy is lower. Using the gross area would overstate available space and could lead to unsafe egress conditions. The other ideas aren’t appropriate here because fixed obstructions reduce usable area, and you still need a method that accounts for that.