Code of Massachusetts Regulations › 780 CMR - STATE BOARD OF BUILDING REGULATIONS AND STANDARDS › Chapter 16 - Structural Design › Section 1604 - GENERAL DESIGN REQUIREMENTS › Subsection 1604.5 - Occupancy category

Current through Register 1525, July 5, 2024
Each building and structure shall be assigned an
occupancy category
in accordance with Table 1604.5.
TABLE 1604.5 OCCUPANCY CATEGORY OF BUILDINGS AND OTHER
				  STRUCTURES
OCCUPANCY
CATEGORY
NATURE OF OCCUPANCY
I
Buildings and other structures that represent a low
							 hazard to human life in the event of failure, including but not limited to:
* Agricultural facilities.
* Certain
							 temporary facilities.
* Minor storage facilities.
II
Buildings and other structures except those listed in
							 Occupancy Categories I, III and IV
III
Buildings and other structures that represent a
							 substantial hazard to human life in the event of failure, including but not
							 limited to:
* Buildings and other structures whose primary
							 occupancy is public assembly with an occupant load greater than 300.
* Buildings and other structures containing elementary school,
							 secondary school or day care facilities with an occupant load greater than 250.
* Buildings and other structures containing adult education
							 facilities, such as colleges and universities, with an occupant load greater
							 than 500.
* Group I-2 occupancies with an occupant
							 load of 50 or more resident patients but not having surgery or emergency
							 treatment facilities.
* Group I-3 occupancies.
* Any
							 other occupancy with an occupant load greater than 5,000a.
*
							 Power-generating stations, water treatment facilities for potable water, waste
							 water treatment facilities and other public utility facilities not included in
							 Occupancy Category IV.
* Buildings and other structures not
							 included in Occupancy Category IV containing sufficient quantities of toxic or
							 explosive substances to be dangerous to the public if released.
IV
Buildings and other structures designated as essential
							 facilities, including but not limited to:
* Group I-2 occupancies
							 having surgery or emergency treatment facilities.
* Fire, rescue,
							 ambulance and police stations and emergency vehicle garages.
*
							 Designated earthquake, hurricane or other emergency shelters.
* Designated emergency preparedness, communications and operations
							 centers and other facilities required for emergency response.
*
							 Power-generating stations and other public utility facilities required as
							 emergency backup facilities for Occupancy Category IV structures.
* Structures containing highly toxic materials as defined by Section 307 where
							 the quantity of the material exceeds the maximum allowable quantities of Table
							 307.1(2).
* Aviation control towers, air traffic control centers
							 and emergency aircraft hangars.
* Buildings and other structures
							 having critical national defense functions.
* Water storage
							 facilities and pump structures required to maintain water pressure for fire
							 suppression.
a. For purposes of occupant load calculation,
							 occupancies required by Table 1004.1.1 to use gross floor area calculations
							 shall be permitted to use net floor areas to determine the total occupant
							 load.
1604.5.1
Multiple occupancies.
Where a building or structure is occupied by two
				or more occupancies not included in the same
occupancy
				category
, it shall be assigned the classification of the highest
occupancy category
corresponding to the various occupancies.
				Where buildings or structures have two or more portions that are structurally
				separated, each portion shall be separately classified. Where a separated
				portion of a building or structure provides required access to, required egress
				from or shares life safety components with another portion having a higher
occupancy category
, both portions shall be assigned to the
				higher
occupancy category
.