780003
2/7/97 (Effective 2/28/97) 780 CMR - Sixth Edition 47
USE OR OCCUPANCY
780 CMR 301.0 GENERAL
of all buildings and
ructures as to use group.
pecifically required by the
rovisions of 780 CMR.
780 CMR 302.0 CLASSIFICATION
which the occupancy most nearly
r
-2,
303.0) -5
2. Use Group B
304.0)
3. Use Group E
4. Use Groups F-1 and F-2
306.0)
-1, H-2,
07.0):
Groups I-1, I-2 and
308.0)
7. Use Group M
R 309.0)
, R-2, R-
R 310.0)
9. Use Groups S-1 and S-2
10.
ous (see 780 CMR 312.0)
tion alternative
of Table 302.1.1 shall not apply.
areas within
and serving a dwelling unit are not required to
comply with 780 CMR 302.1.1.
ble 302 .1
S CCUPA
b a n
HAPTER 3C
301.1 Scope: The provisions of 780 CMR 3 shall
control the classification
st
301.2 Application of other laws: The provisions of
780 CMR 3 shall not be deemed to nullify any
provisions of the zoning law, ordinance of any
municipality in the Commonwealth of
Massachusetts, or any other statute of the
jurisdiction pertaining to the location or occupancy
of buildings, except as is s
p
302.1 General: All structures shall be classified
with respect to occupancy in one or more of the use
groups listed below. Where a structure is proposed
for a purpose which is not specifically provided for
in 780 CMR, such structure shall be classified in the
use group
esembles.
1. Assembly: Use Groups A-1, A
(see 780 CMR A-3, A-4 and A
Business:
(see 780 CMR
Educational:
(see 780 CMR 305.0)
Factory and Industrial:
(see 780 CMR
5. High Hazard Use Groups H
(see 780 CMR 3 H-3 and H-4
6. Institutional: Use
(see 780 CMR I-3
Mercantile:
(see 780 CM
8. Residential: Use Groups R-1
(see 780 CM 3, R-4 and R-5
Storage:
(see 780 CMR 311.0)
Utility and Miscellane- Use Group U
302.1.1 Specific occupancy areas: Specific
occupancy areas which are incidental to the main
use group shall be separated and protected in
accordance with Table 302.1.1 and shall be
classified in accordance with the main use group
of the portion of the building in which the specific
occupancy area is located. Where the building, or
portion thereof, containing the specific occupancy
area is required to be protected with an automatic
fire suppression system, the separa
Exception: Specific occupancy
Ta
PECIFIC O
.1
NCY AREAS
Room or area
Separation /protectio
s
ess than those
Us
automatic fire sup-
pression system
All use groups:
Paint shops in occupancies
oth- er than Use Group F
employing hazardous material
in quanti-ties l
2 hours; or 1 hour and
which cause classification as
e Group H
W linen collec- aste and soiled
tion rooms and chute term-
ination rooms
1 hour and automatic fire
suppression system
te
access rooms
Waste and soiled linen chu
1 hour
Boiler and furnace rooms
1 hour; or automatic fire
suppression system
Incinerator rooms
U
R-2:
St
e feet in area but not
t in
hours and automatic fire
1
suppression system
with smoke partitions
se Groups A, B, E, I-1, R-1,
orage rooms more than 50
squar
more than 100 square fee
area
2
suppression system
hour; or automatic fire
Storage rooms more than
100 square feet in area
Automatic fire suppres-
sion system with smoke
partitions
2 hours;
Physical plant maintenance
shop and workshop
Bo
or 1 hour and au-
matic fire suppression
Use Groups I-2, I-3:
iler and furnace rooms
to
system
1 hour and automatic fire
suppression system Handicraft shops, kitchens,
and employee locker rooms
1 fire hour; or automatic
suppression system with
smoke partitions
Laundries greater than 100
square feet in area
1 hour and automatic fire
suppression system
Storage rooms more than 50
square feet in area but not
more than 100 square feet in
area
Automatic fire suppres-
sion system with smoke
partitions
Storage rooms more than 100
square feet in area
1 hour and automatic fire
suppression system
Physical plant maintenance
shop and workshop
1 hour and automatic fire
suppression system
1 hour; or automa
U
ator-
than those
tic fire
ppression system with
oke partitions
se Group I-2:
Gift/retail shops and labor
ies employing hazardous
quantities less
su
sm
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
THE MASSACHUSETTS STATE BUILDING CODE
48 780 CMR - Sixth Edition 9/9/05 (Effective 8/26/05)
which cause classification as
U
Use Group H
se Group I-3 padded cells 1 hour and automatic fire
system
Note a. For requirements for fireresistance rated
se ee 780 CMR
302.1.1.1.
Note b. 1 square foot = 0.093 m2.
parations and smoke partitions s
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
USE OR OCCUPANCY
2/7/97 (Effective 2/28/97) 780 CMR - Sixth Edition 49
302.1.1.1 Separation: Where Table 302.1.1
requires a fireresistance rated separation, the
specific occupancy area shall be separated from
the remainder of the building with fire
separation assemblies (see 780 CMR 709.0).
Where Table 302.1.1 requires smoke partitions,
the smoke partitions shall be constructed of
materials consistent with the type of
construction and shall be capable of resisting
the passage of smoke. The smoke partitions
shall extend from the floor to the underside of
the fireresistance rated floor/ceiling or
roof/ceiling assembly or to the underside of the
floor or roof deck above. All doors shall be self-
closing or automatic-closing upon detection of
smoke.
302.1.2 Accessory areas: Except for accessory
areas of Use Group H in accordance with
780 CMR 302.1.2.1 and specific occupancy areas
indicated in 780 CMR 302.1.1, where the area
devoted to an accessory occupancy does not
occupy more than 10% of any fire area nor more
than 10% of the allowable area permitted by
780 CMR 503.0 based on the accessory use group,
a fire separation assembly shall not be required
between the main use group and accessory areas.
The required type of construction and the
automatic fire suppression requirements in
780 CMR 904.0 shall be based on the main use
group of the fire area.
302.1.2.1 High-hazard uses: In buildings that
are three stories or less in height and equipped
throughout with an automatic suppression
system in accordance with 780 CMR 9, an
occupancy in Use Group F or S is permitted to
have accessory areas of Use Group H-2, H-3 or
H-4, provided that such areas do not occupy
more than 10% of any fire area nor more than
10% of the allowable area permitted by
780 CMR 503.0 based on the use group of the
accessory area. A fire separation assembly shall
not be required between the F or S use group
and the accessory H use group. The maximum
quantity of hazardous materials within the
accessory H use group shall not exceed twice
the permitted exempt amount specified in Table
307.8(1) or Table 307.8(2). The required type of
construction shall be based on the main use
group of the fire area.
302.2 Mixed use: All buildings and structures that
include more than one use group shall be further
designated as a mixed use and shall comply with
780 CMR 313.0. Specific occupancy areas and
accessory areas complying with 780 CMR 302.1.1
and 302.1.2, respectively, shall be classified in
accordance with the main use group.
780 CMR 303.0 ASSEMBLY USE
GROUPS
303.1 General: All structures which are designed or
occupied for the gathering together of persons for
purposes such as civic, social or religious functions,
recreation, food or drink consumption or awaiting
transportation, shall be classified as Use Group A-1,
A-2, A-3, A-4 or A-5. A room or space used for
assembly purposes by less than 50 persons and
which is accessory to another use group shall be
included as a part of that main use group. Other
buildings or structures which accomodate less than
50 but would otherwise qualify as places of
assembly, shall be classified in Use Group B. The
term "Use Group A" shall include Use Groups A-1,
A-2, A-3, A-4 and A-5.
303.2 Use Group A-1, theaters: This use group
shall include all theaters and all other buildings and
structures intended for the production and viewing
of performing arts or motion pictures; and which are
usually provided with fixed seats-including theaters,
motion picture theaters and television and radio
studios admitting an audience. Stages and platforms
shall comply with 780 CMR 412.0.
303.3 Use Group A-2 structures: This use group
shall include all buildings and places of public
assembly, without theatrical stage accessories,
designed for occupancy as dance halls, nightclubs
and for similar purposes, including all rooms,
lobbies and other spaces connected thereto with a
common means of egress and entrance.
303.4 Use Group A-3 structures: This use group
shall include all buildings with or without an
auditorium in which persons assemble for
amusement, entertainment or recreation purposes as
well as incidental motion picture, dramatic or
theatrical presentations, lectures or other similar
purposes without theatrical stage other than a raised
platform; and which are principally occupied
without permanent seating facilities, including art
galleries, exhibition halls, museums, lecture halls,
libraries, restaurants other than nightclubs, and rec-
reation centers; and buildings designed for similar
assembly purposes, including passenger terminals.
303.5 Use Group A-4 structures: This use group
shall include all buildings and structures which are
occupied exclusively for the purpose of worship or
other religious services.
303.6 Use Group A-5, outdoor assembly: This use
group shall include structures utilized for outdoor
assembly intended for participation in or reviewing
activities, including grandstands (780 CMR 1013.0),
bleachers (780 CMR 1013.0), coliseums, stadiums,
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
THE MASSACHUSETTS STATE BUILDING CODE
50 780 CMR - Sixth Edition 9/9/05 (Effective 8/26/05)
amusement park structures (780 CMR 413.0) and
fair or carnival structures. Such structures shall
comply with all pertinent provisions of 780 CMR.
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
USE OR OCCUPANCY
2/7/97 (Effective 2/28/97) 780 CMR - Sixth Edition 51
780 CMR 304.0 BUSINESS USE GROUP
304.1 General: All buildings and structures which
are occupied for the transaction of business, for the
rendering of professional services, or for other
services that involve stocks of goods, wares or mer-
chandise in limited quantities which are incidental to
office occupancies or sample purposes, shall be clas-
sified as Use Group B. (Also see 780 CMR 303.1.)
304.2 List of business occupancies: The
occupancies listed in Table 304.2 are indicative of
and shall be classified as Use Group B.
Table 304.2
BUSINESS OCCUPANCIES
Airport traffic control
towers
Animal hospitals, kennels,
pounds
Automobile and other
motor vehicle showrooms
Banks
Barber shops
Beauty shops
Car wash
Civic administration
Clinic, outpatient
Dry-cleaning; pickup and
delivery stations and
self-service
Electronic data processing
Fire stations
Florists and nurseries
Laboratories; testing and
research
Laundries; pickup and deliv-
ery stations and self-
service
Police stations
Post offices
Print shops
Professional services; attor-
ney, dentist, physician,
engineer, etc.
Radio and television
stations
Telecommunications
equipment building
780 CMR 305.0 EDUCATIONAL USE
GROUP
305.1 General: All structures other than those
occupied for business training or vocational training,
which accommodate more than five persons for
educational purposes through the 12th grade, shall
be classified as Use Group E.
Exception: A room or space occupied for educa-
tional purposes by less than 50 persons, five years
of age or more, and which is accessory to another
use group shall be classified as a part of the main
use group.
305.1.1 Day care facilities: A child day care
cen-ter which provides care for children more
than two years nine months shall be classified as
use Group E.
305.2 Business or vocational training: Structures
occupied for business training or vocational training
shall be classified in the same use group as the
business or vocation taught.
780 CMR 306.0 FACTORY AND
INDUSTRIAL USE GROUPS
306.1 General: All structures in which occupants
are engaged in work or labor in the fabricating,
assemb-ling or processing of products or materials,
shall be classified as Use Group F-1 or F-2. This
includes, among others, factories, assembling plants,
industrial laboratories and all other industrial and
manufac-turing occupancies. The term "Use Group
F" shall include Use Groups F-1 and F-2.
306.2 Use Group F-1 structures: Factory and
industrial occupancies which are not otherwise
classified as low-hazard, Use Group F-2, shall be
classified as a moderate-hazard factory and
industrial occupancy, Use Group F-1. The
manufacturing processes listed in Table 306.2 are
indicative of and shall be classified as Use Group F-
1.
Table 306.2
MODERATE-HAZARD FACTORY AND
INDUSTRIAL OCCUPANCIES
Aircraft
Appliances
Athletic equipment
Automobiles and other motor
vehicles
Bakeries
Beverages, alcoholic
Bicycles
Boat building
Boiler works
Brooms or brushes
Business machines
Cameras and photo equipment
Canneries, including food
products
Clothing
Condensed and powdered
milk manufacture
Construction and agricultural
machinery
Disinfectants
Dry cleaning using other than
flammable liquids in clean-
ing or dyeing operations or
other than classified in 780
CMR 307.0
Electric light plants and
power houses
Electrolytic reducing works
Electronics
Engines, including rebuilding
Film, photographic
Food processing
Furniture
Hemp and jute products
Laundries
Leather and tanneries, ex-
cluding enameling or
japanning
Machinery
Millwork and woodworking,
wood distillation
Motion picture and television
filming
Musical instruments
Optical goods
Paper mills or products
Plastic products
Printing or publishing
Recreational vehicles
Refuse incinerators
Shoes
Soaps and detergents
Sugar refineries
Textile mills, including
canvas, cotton, cloth,
bagging, burlap, carpets
and rags
Tobacco
Trailers
Upholstery and manufactur-
ing shops
306.3 Use Group F-2 structures: Factory and
industrial occupancies which involve the fabrication
or manufacturing of noncombustible materials that,
during finishing, packing or processing, do not
contribute to a significant fire hazard, shall be
classified as Use Group F-2. The manufacturing
processes listed in Table 306.3 are indicative of and
shall be classified as Use Group F-2.
Table 306.3
LOW-HAZARD FACTORY AND
INDUSTRIAL OCCUPANCIES
Beverages, nonalcoholic
Brick and masonry
Gypsum
Ice
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
THE MASSACHUSETTS STATE BUILDING CODE
52 780 CMR - Sixth Edition 9/9/05 (Effective 8/26/05)
Ceramic products
Foundries
Glass products
Metal fabrication and
assembly
Water pumping plants
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
USE OR OCCUPANCY
2/7/97 (Effective 2/28/97) 780 CMR - Sixth Edition 53
780 CMR 307.0 HIGH-HAZARD USE
GROUPS
307.1 General: All structures which are occupied
for the manufacturing, processing, generation,
storage or other use of hazardous materials in
excess of the exempt quantities specified in
780 CMR 307.8 shall be classified as Use Group H-
1, H-2, H-3 or H-4 in accordance with the hazards
presented by each material as described in 780 CMR
307.3 through 307.6. The term "Use Group H" shall
include Use Groups H-1, H-2, H-3 and H-4.
307.1.1 Information required: Separate floor
plans shall be submitted for buildings and
structures with an occupancy in Use Group H,
identifying the locations of anticipated contents
and processes so as to reflect the nature of each
occupied portion of every building and structure.
A report identifying all hazardous materials
including, but not limited to, materials of Use
Group H to be stored or utilized, shall be
submitted and the methods of protection from
such hazards shall be indicated on the
construction documents.
307.2 Definitions: The following words and terms
shall, for the purposes of 780 CMR 3 and as used
elsewhere in 780 CMR, have the meanings shown
herein.
Aerosol: A product that is dispensed from an
aerosol container by a propellant.
Aerosol container: Metal cans, glass or plastic
bottles designed to dispense an aerosol. Metal
cans shall be limited to a maximum size of 33.8
fluid ounces (1000 ml). Glass or plastic bottles
shall be limited to a maximum size of four fluid
ounces (118 ml).
Barricade: A structure that consists of a
combination of walls, floor and roof, which is
designed to withstand the rapid release of energy
in an explosion and which is fully confined,
partially vented or fully vented; or other effective
method of shielding from explosive materials by a
natural or artificial barrier.
Boiling point: The temperature at which the vapor
pressure of a liquid equals the atmospheric
pressure of 14.7 pounds per square inch (psia) or
760 mm of mercury. Where an accurate boiling
point is unavailable for the material in question,
or for mixtures which do not have a constant
boiling point, for the purposes of this
classification, the 10% of a distillation performed
in accordance with ASTM D86 listed in
Appendix A shall be used as the boiling point of
the liquid.
Closed system: The use of a solid or liquid
hazardous material in a closed vessel or system
that remains closed during normal operations
where vapors emitted by the product are not
liberated outside of the vessel or system and the
product is not exposed to the atmosphere during
normal operations; and all uses of compressed
gases. Examples of closed systems for solids and
liquids include product conveyed through a piping
system into a closed vessel, system or piece of
equipment.
Combustible dusts: Dusts and any similar solid
material sufficiently comminuted for suspension
in still air which, when so suspended, is capable
of self-sustained combustion.
Combustible fibers: Includes readily ignitable and
free-burning fibers such as cotton, sisal,
henequen, jute, hemp, tow, cocoa fiber, oakum,
baled waste, baled wastepaper, kapok, hay, straw,
excelsior, Spanish moss and other like material.
Combustible liquids: Any liquids having a flash
point at or above 100°F (38°C) shall be known as
Class II or III liquids. Combustible liquids shall
be divided into the following classifications:
Class II: Liquids having flash points at or above
100°F (38°C) and below 140°F (60°C).
Class IIIA: Liquids having flash points at or above
140°F (60°C) and below 200°F (93°C).
Class IIIB: Liquids having flash points at or above
200°F (93°C).
Compressed gas: A gas or mixture of gases as
contained having an absolute pressure exceeding
40 psi at 70°F (276 kPa at 21°C) or, regardless of
the pressure at 70°F (21°C), having an absolute
pressure exceeding 140 psi at 130°F (965 kPa at
54°C); or any liquid material having a vapor
pressure exceeding 40 psi absolute at 100°F (276
kPa at 38°C) as determined by ASTM D323 listed
in Appendix A
Control area: Spaces within a building which are
enclosed and bounded by exterior walls, fire
walls, fire separation assemblies and roofs, or a
combination thereof, where quantities of
hazardous materials not exceeding the exempt
amounts are stored, dispensed, used or handled.
Corrosive: A chemical that causes visible
destruction of, or irreversible alterations in, living
tissue at the point of contact. A chemical shall be
considered a corrosive if, when tested on the
intact skin of albino rabbits by the test method
described by DOTn 49 CFR; Part 173 listed in
Appendix A, such chemical destroys or changes
irreversibly the structure of the tissue at the point
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
THE MASSACHUSETTS STATE BUILDING CODE
54 780 CMR - Sixth Edition 9/9/05 (Effective 8/26/05)
of contact following an exposure period of four
hours. This term shall not refer to action on
inanimate surface.
Cryogenic liquids (flammable or oxidizing): Any
liquid that has a boiling point below -200°F (-
129°C).
Deflagration: An exothermic reaction, such as the
extremely rapid oxidation of a flammable dust or
vapor in air, in which the reaction progresses
through the unburned material at a rate less than
the velocity of sound. A deflagration can have an
explosive effect.
Detached storage building: A separate single-story
building, without a basement or crawl space, used
for the storage of hazardous materials and located
an approved distance from all structures.
Detonation: An exothermic reaction characterized
by the presence of a shock wave in the material
which establishes and maintains the reaction. The
reaction zone progresses through the material at a
rate greater than the velocity of sound. The
principal heating mechanism is one of shock
compression. detonations have an explosive
effect.
Dispensing: The pouring or transferring of any
material from a container, tank or similar vessel,
whereby vapors, dusts, fumes, mists or gases are
liberated to the atmosphere.
Explosive: Any chemical compound, mixture or
device, the primary or common purpose of which
is to function by explosion. The term includes, but
is not limited to, dynamite, black powder, pellet
powder, initiating explosives, detonators, safety
fuses, squibs, detonating cord, igniter cord and
igniters.
The term "explosive" includes any material
determined to be within the scope of USC Title
18; Chapter 40 listed in Appendix A and also
includes any material classified as an explosive by
the Hazardous Material Regulations of DOTn 49
CFR listed in Appendix A.
Flammable: Capable of being readily ignited from
common sources of heat or at a temperature of
600°F (316°C) or less.
Flammable compressed-gas: Either a mixture of
13% or less (by volume) with air forms a
flammable mixture, or the flammable range with
air is wider than 12%, regardless of the lower
limitation. These limitations shall be determined
at atmospheric temperature and pressure.
Flammable liquids: Any liquid that has a flash point
below 100°F (38°C), and has a vapor pressure not
exceeding 40 psia (276 kPa) at 100°F (38°C).
Flammable liquids shall be known as Class I
liquids and shall be divided into the following
classifications:
Class IA: Liquids having a flashpoint below 73°F
(23°C) and having a boiling point below 100°F
(38°C).
Class IB: Liquids having a flash point below 73°F
(23°C) and having a boiling point at or above
100°F. (38°C).
Class IC: Liquids having a flash point at or above
73°F (23°C) and below 100°F (38 °C).
Flammable solid: A solid, other than a blasting
agent or explosive, that is capable of causing fire
through friction, absorption of moisture,
spontaneous chemical change, or retained heat
from manufacturing or processing. or which has
an ignition temperature below 212°F ( 100°C) or
which burns so vigorously and persistently when
ignited as to create a serious hazard. A chemical
shall be considered a flammable solid as
determined in accordance with the test method of
CPSC 16 CFR; Part 1500.44 listed in
Appendix A, if it ignites and burns with a self-
sustained flame at a rate greater than 0.1 inch (3
mm) per second along its major axis.
Flash point: The minimum temperature in degrees
Fahrenheit at which a flammable liquid will give
off sufficient vapors to form an ignitable mixture
with air near the surface or in the container, but
will not sustain combustion. The flash point of a
liquid shall be determined by appropriate test
procedure and apparatus as specified in ASTM
D56 and ASTM D93 listed in Appendix A.
Hazardous materials: Those chemicals or
substances which are physical hazards or health
hazards as defined and classified in 780 CMR 3
and the fire prevention code listed in Appendix A,
whether the materials are in usable or waste
condition.
Health hazard: A classification of a chemical for
which there is statistically significant evidence
that acute or chronic health effects are capable of
occurring in exposed persons. The term "health
hazard" includes chemicals which are
carcinogens, toxic or highly toxic agents,
reproductive toxins, irritants, corrosives,
sensitizers, hepatotoxins, nephrotoxins,
neurotoxins, agents which are capable of acting
on the hematopoietic system, and agents which
damage the lungs, skin, eyes or mucous
membranes.
Highly toxic: A chemical falling within any of the
following categories is considered highly toxic.
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
USE OR OCCUPANCY
2/7/97 (Effective 2/28/97) 780 CMR - Sixth Edition 55
1. A chemical that has a median lethal dose
(LD50) of 50 milligrams or less per kilogram of
body weight when administered orally to
albino rats weighing between 200 and 300
grams each.
2. A chemical that has a median lethal dose
(LD50) of 200 milligrams or less per kilogram
of body weight when administered by
continuous contact for 24 hours (or less if
death occurs within 24 hours) with the bare
skin of albino rabbits weighing between two
and three kilograms each.
3. A chemical that has a median lethal
concentration (LC50) in air of 200 parts per
million by volume or less of gas or vapor, or
two milligrams per liter or less of mist, fume or
dust, when administered by continuous
inhalation for one hour (or less if death occurs
within one hour) to albino rats weighing
between 200 and 300 grams each.
Incompatible materials: Materials which, when
mixed, have the potential to react in a manner that
generates heat, fumes, gases or by-products which
are hazardous to life or property.
Irritant: A chemical, which is not corrosive, but
which causes a reversible inflammatory effect on
living tissue by chemical action at the point of
contact. A chemical shall be considered an irritant
if, when tested on the intact skin of albino rabbits
by the test method of CPSC 16 CFR; Part 1500.41
listed in Appendix A for four hours exposure, it
results in an empirical score of five or more. A
chemical is an eye irritant if so determined by the
procedure in CPSC 16 CFR; Part 1500.42 listed in
Appendix A.
Open system: The use of a solid or liquid hazardous
material in a vessel or system that is continuously
open to the atmosphere during normal operations
and where vapors are liberated, or the product is
exposed to the atmosphere during normal
operations. Examples of open systems for solids
and liquids include dispensing from or into open
beakers or containers, dip tank and plating tank
operations.
Organic peroxide: An organic compound that
contains the bivalent double-bonded oxygen
structure and which is considered to be a
structural derivative of hydrogen peroxide where
one or both of the hydrogen atoms have been
replaced by an organic radical.
Unclassified detonable: Organic peroxides which
are capable of detonation. These peroxides
present an extremely high explosion hazard
through rapid explosive decomposition.
Class I: Class I organic peroxides are capable of
deflagration, but not detonation. These peroxides
present a high explosion hazard through rapid
decomposition.
Class II: Class II organic peroxides burn very
rapidly and present a severe reactivity hazard.
Class III: Class III organic peroxides burn rapidly
and present a moderate reactivity hazard.
Oxidizer: A chemical other than a blasting agent or
explosive that initiates or promotes combustion in
other materials, thereby causing fire either of
itself or through the release of oxygen or other
gases.
Class 4: An oxidizer that can undergo an
explosive reaction due to contamination or
exposure to thermal or physical shock.
Additionally, the oxidizer will enhance the
burning rate and is capable of causing
spontaneous ignition of combustibles.
Class 3: An oxidizer that will cause a severe
increase in the burning rate of combustible
materials with which the oxidizer comes in
contact or that will undergo vigorous self-
sustained decomposition due to contamination or
exposure to heat.
Class 2: An oxidizer that will cause a moderate
increase in the burning rate or that is capable of
causing spontaneous ignition of combustible
materials with which the oxidizer comes in
contact.
Class 1: An oxidizer whose primary hazard is a
slight increase in the burning rate but which does
not cause spontaneous ignition when the oxidizer
comes in contact with combustible material.
Physical hazard: A chemical for which there is
evidence in the referenced standards listed in
Appendix A that it is a combustible liquid,
compressed gas, cryogenic, explosive, flammable
gas, flammable liquid, flammable solid, organic
peroxide, oxidizer, pyrophoric or unstable
(reactive) or water-reactive material.
Pyrophoric: A material that will spontaneously
ignite in air at or below a temperature of 130°F
(54°C).
Radioactive material: Any material or combination
of material that spontaneously emits ionizing
radiation.
Sensitizer: A chemical that causes a substantial
proportion of exposed people or animals to
develop an allergic reaction in normal tissue after
repeated exposure to the chemical.
Tires, bulk storage of: Storage of 10,000 or more
average-sized passenger vehicle tires weighing
approximately 25 pounds (11 kg) each (see
780 CMR 307.5).
Toxic: A chemical that is within any of the following
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
THE MASSACHUSETTS STATE BUILDING CODE
56 780 CMR - Sixth Edition 9/9/05 (Effective 8/26/05)
categories shall be considered toxic:
1. A chemical that has a median lethal dose
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
USE OR OCCUPANCY
2/7/97 (Effective 2/28/97) 780 CMR - Sixth Edition 57
(LD50) of more than 50 milligrams per kilogram
but not more than 500 milligrams per kilogram of
body weight when administered orally to albino
rats weighing between 200 and 300 grams each.
2. A chemical that has a median lethal dose
(LD50) of more than 200 milligrams per
kilogram but not more than 1,000 milligrams
per kilogram of body weight when
administered by continuous contact for 24
hours (or less if death occurs within 24 hours)
with the bare skin of albino rabbits weighing
between two and three kilograms each.
3. A chemical that has a median lethal
concentration (LC50) in air of more than 200
parts per million but not more than 2,000 parts
per million by volume of gas or vapor, or more
than two milligrams per liter but not more than
20 milligrams per liter of mist, fume or dust,
when administered by continuous inhalation
for one hour (or less if death occurs within I
hour) to albino rats weighing between 200 and
300 grams each.
Unstable (reactive) material: A material which, in
the pure state or as commercially produced, will
vigorously polymerize, decompose or condense,
become self-reactive, or otherwise undergo a
violent chemical change under conditions of
shock, pressure or temperature.
Class 4: Materials that in themselves are readily
capable of detonation or explosive decomposition
or explosive reaction at normal temperatures and
pressures. This class includes, among others,
materials that are sensitive to localized thermal or
mechanical shock at normal temperatures and
pressures.
Class 3: Materials that in themselves are capable
of detonation or explosive decomposition or
explosive reaction, but that require a strong
initiating source or that must be heated under
confinement before initiation. This class includes,
among others, materials that are sensitive to
thermal or mechanical shock at elevated
temperatures and pressures.
Class 2: Materials that readily undergo violent
chemical change at elevated temperatures and
pressures. This class includes, among others,
materials that exhibit an exotherm at temperatures
less than or equal to 150°C when tested by
differential scanning calorimetry.
Class 1: Materials that in themselves are normally
stable, but that can become unstable at elevated
temperatures and pressures. This class includes,
among others, materials that change or decompose
on exposure to air, light or moisture, and materials
that exhibit an exotherm at temperatures greater
than 150°C, but less than or equal to 300°C, when
tested by differential scanning calorimetry.
Water-reactive materials: A chemical that reacts
with water to release a gas that is either
flammable or presents a health hazard.
Class 3: Materials which react explosively with
water without requiring heat or confinement.
Class 2: Materials which are capable of forming
potentially explosive mixtures with water.
307.3 Use Group H-1 structures: All buildings and
structures which contain materials that present a
detonation hazard, shall be classified as Use Group
H- 1. Such materials shall include but are not limited
to:
Explosives
Organic Peroxides, unclassified detonable
Oxidizers, Class 4
Unstable (reactive) materials, Class 3 detonable,
and Class 4
Detonable pyrophoric materials
307.4 Use Group H-2 structures: All buildings and
structures which contain materials that present a
deflagration hazard or a hazard from accelerated
burning, shall be classified as Use Group H-2. Such
materials shall include but are not limited to:
Combustible dusts
Combustible liquids, Class II and Class IIIA
Cryogenic liquids, flammable or oxidizing
Flammable gases
Flammable liquids
Organic peroxides, Class I and Class II
Oxidizers, Class 3
Oxidizing gases
Pyrophoric liquids, solids and gases,
nondetonable
Unstable (reactive) materials, Class 3,
nondetonable
307.5 Use Group H-3 structures: All buildings and
structures which contain materials that readily
support combustion or present a physical hazard,
shall be classified as Use Group H-3. Such materials
shall include but are not limited to:
Aerosols, except that Level 1 aerosols defined in
the fire prevention code listed in Appendix A shall
be classified as Use Group S-1 or F-1
Combustible fibers
Combustible liquids, Class IIIB
Flammable solids
Organic peroxides, Class III
Oxidizers, Class 1 and Class 2
Tires, bulk storage of
Unstable (reactive) materials, Class 1 and Class 2
Water-reactive materials, Class 2 and Class 3
307.6 Use Group H-4 structures: All buildings and
structures which contain materials that are health
hazards, shall be classified as Use Group H-4. Such
materials shall include but are not limited to:
Corrosives
Highly toxic materials
Irritants
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
THE MASSACHUSETTS STATE BUILDING CODE
58 780 CMR - Sixth Edition 9/9/05 (Effective 8/26/05)
Radioactive materials
Sensitizers
Toxic materials
307.7 Multiple hazards: All buildings and
structures containing a material or materials
representing hazards that are classified in one or
more of Use Groups H-1, H-2, H-3 and H-4, shall
conform to the code requirements for each of the use
groups so classified.
307.8 Exceptions: The following shall not be
classified in Use Group H, but shall be classified in
the use group which they most nearly resemble.
High-hazard materials of any quantity shall conform
to the requirements of 780 CMR, including
780 CMR 417.0, and the fire prevention code listed
in Appendix A.
1. All buildings and structures which contain not
more than the exempt quantities of high-hazard
materials as shown in Tables 307 .8(1) and
307.8(2) provided that such buildings are
maintained in accordance with the fire
prevention code listed in Appendix A.
2. Buildings utilizing control areas in accordance
with 780 CMR 417.2 which contain not more
than the exempt quantities of high-hazard
materials as shown in Tables 307.8(1) and
307.8(2).
3. Buildings and structures occupied for the
storage of 10,000 or less vehicle tires weighing
approximately 25 pounds (11 kg) each,
provided that such buildings are equipped
throughout with an automatic sprinkler system
in accordance with 780 CMR 906.2.1.
4. Buildings and structures occupied for the
application of flammable finishes, provided that
such buildings or areas conform to the
requirements of 780 CMR 419.0 and NFiPA 33,
NFiPA 34 and the fire prevention code listed in
Appendix A.
5. Rooms containing flammable liquids in tightly
closed containers of 1-gallon capacity (0.0038
m) or less for retail sale or private utilization on
the premises and in quantities not exceeding
two gallons per square foot (0.082 m3/m2 ) of
room area.
6. Retail paint salesrooms with quantities of paint
not exceeding two-gallons per square foot
(0.082 m3/m2) of room area.
7. Closed systems housing flammable or
combustible liquids or gases utilized for the
operation of machinery or equipment.
8. Cleaning establishments which utilize
combustible liquid solvents having a flash point
of 140°F (60°C) or higher in closed systems
employing equipment listed by an approved
testing agency, provided that this occupancy is
separated from all other areas of the building by
one-hour fireresistance rated fire separation
assemblies.
9. Cleaning establishments which utilize a liquid
solvent having a flash point at or above 200°F
(93°C).
10. Liquor stores and distributors without bulk
storage.
11. Refrigeration systems.
12. The storage or utilization of materials for
agricultural purposes on the premises.
13. Stationary batteries utilized for facility
emergency power, uninterrupted power
supply or telecommunication facilities
provided that the batteries are provided with
safety venting caps and ventilation is
provided in accordance with the mechanical
code listed in Appendix A.
14. Corrosives, irritants and sensitizers shall not
include personal or household products in
their original packaging used in retail display
or commonly used building materials.
15. Buildings and structures occupied for aerosol
manufacturing or storage shall be classified
as Use Group F-1 or S-1, provided that such
buildings conform to the requirements of
NFiPA 30 and the fire prevention code listed
in Appendix A.
780 CMR 308.0 INSTITUTIONAL USE
GROUPS
308.1 General: All structures in which people
suffering from physical limitations because of health
or age are harbored for medical or other care or
treatment, or in which people are detained for penal
or correction purposes, or in which the liberty of the
inmates is restricted, shall be classified as Use
Group I-1, I-2 or I-3. The term "Use Group I" shall
include Use Groups I-1, I-2 and I-3.
308.2 Use Group I-1: Except as modified by the
provisions of 780 CMR 4, Special Use and
Occupancy, this use group shall include buildings
and structures which house six or more individuals
who, because of age, mental disability or other
reasons, must live in a supervised environment but
who are physically capable of responding to an
emergency situation without personal assistance.
Except as specified otherwise by the requirements
of 780 CMR 4, Special Use and Occupancy, where
accommodating persons of the above description,
the following types of facilities shall be classified as
I-1 facilities, board and care facilities, half-way
houses, group homes, social rehabilitation facilities,
alcohol and drug centers and convalescent facilities.
A facility such as the above with five or less
occupants shall be classified as a residential use
group.
308.3 Use Group I-2: This use group shall include
buildings and structures used for medical, surgical,
psychiatric, nursing or custodial care on a 24-hour
basis of six or more persons who are not capable of
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
USE OR OCCUPANCY
2/7/97 (Effective 2/28/97) 780 CMR - Sixth Edition 59
self-preservation. Where accommodating persons of
the above description, the following types of
facilities shall be classified as I-2 facilities:
hospitals, nursing homes (both intermediate care
facilities and skilled nursing facilities), mental
hospitals and detoxification facilities. A facility such
as the above with five or less occupants shall be
classified as a residential use group.
308.3.1 Child care facility: A child day care
center which accommodates children two years
nine months of age or less shall be classified as
Use Group I-2.
308.4 Use Group I-3: This use group shall include
buildings and structures which are inhabited by six
or more persons who are under some restraint or
security. An I-3 facility is occupied by persons who
are generally incapable of self-preservation due to
security measures not under the occupants' control.
Where accommodating persons of the above
description, the following types of facilities shall be
classified as I-3 facilities: prisons, jails,
reformatories, detention centers, correctional centers
and prerelease centers. Buildings of Use Group I-3
shall be classified as one of the occupancy
conditions indicated in 780 CMR 308.4.1 through
308.4.5 (see 780 CMR 410.0).
308.4.1 Occupancy Condition I: This occupancy
condition shall include all buildings in which free
movement is allowed from sleeping areas, and
other spaces where access or occupancy is
permitted, to the exterior via means of egress
without restraint. An Occupancy Condition I
facility shall be classified as Use Group R.
308.4.2 Occupancy Condition II: This
occupancy condition shall include all buildings in
which free movement is allowed from sleeping
areas and any other occupied smoke compartment
to one or more other smoke compartments. Egress
to the exterior is impeded by locked exits.
308.4.3 Occupancy Condition III: This
occupancy condition shall include all buildings in
which free movement is allowed within individual
smoke compartments, such as within a residential
unit comprised of individual sleeping rooms and
group activity spaces, where egress is impeded by
remote-controlled release of means of egress from
such smoke compartment to another smoke
compartment
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
THE MASSACHUSETTS STATE BUILDING CODE
60 780 CMR - Sixth Edition 9/9/05 (Effective 8/26/05)
Table 307.8(1)
EXEMPT AMOUNTS OF HAZARDOUS MATERIALS, LIQUIDS
AND CHEMICALS PRESENTING A PHYSICAL HAZ D AR
MAXIMUM QUANTITIES PER CONTROL AREAa,k
Storageb
Closed systemsb
Open systemsb
Material
Class
Use
Groups
solid
pounds
(cubic
feet)
liquid
gallons
(pounds)
gas
(Cubic
feet)
Solid
pounds
(cubic
feet)
Liquid
gallons
(pounds)
Gas cubic
feet
Solid
pounds
(cubic
feet)
liquid
gallons
(pounds)
Combustiblec liquid
II
IIIA
IIIB
H-2
H-2
H-3
NA
120d,e
330d,e
13,200e,f
NA
NA
120d
330d
13,200f
NA
NA
30d
80d
3,300f
Conbustible
dust pounds
er 1,00 feet p H-2 1g NA NA 1g NA NA 1g NA
Combustible
iber f
loose
Baled
H-3
(100)
(1,000)
NA
NA
(100)
(1,000)
NA
NA
(20)
(200)
NA
Cryogenics,
flammible or
xidizing o
H-2
NA
45d
NA
NA
45d
NA
NA
10d
Explosives H-1 1e,h,i (1)e,h,i NA ¼h (¼)h NA ¼h (¼)h
Flammable
as g
Gaseous
Liquified H-2 NA
NA
30d,e
1,000d,e
NA NA
NA
30d,e
750d,e
NA NA NA
Flammible
liquidc
IA
IB
IC H-2 NA
30d,e
60d,e
90d,e
NA
NA
30d
60d
90d NA NA
10d
15d
20d
Combination
IA, IB, IC) (
H-2
NA
120d,e,j
NA
NA
120d,j
NA
NA
30d,j
Flammible
olid s
H-2
125d,e
NA
NA
25d
NA
NA
25d
NA Organic
peroxide
UD
I
II
III
H-1
H-2
H-3
H-3
1e,h
5d,e
50d,e
125d,e
(1)e,h
(5)d,e
(50)d,e
(125)d,e NA
¼h
1d
50d
125d
(¼)h
(1)d
(50)d
(125)d NA
¼h
1d
10d
25d
(¼h)
(1)d
(10)d
(25)d
Oxidizer 4
3
2
1
H-1
H-2
H-3
H-3
1e,h
10d,e
250d,e
1,000d,e
(1)e,h
(10)d,e
(250)d,e
(1,000)d,e NA
¼h
2d
250d
1,000d
(¼)h
(2)d
(250)d
(1,000)d NA
¼h
2d
50d
200d
(¼)h
(2)d
(50)d
(200)d
Oxidizer -
as g
Gaseous
Liquified H-2 NA
NA
15d,e
1,500d,e
NA NA
NA
(15)d,e
1,500d,e
NA NA NA
Pyrophoric
H-2
4e,h
(4)e,h
50e,h
1h
(1)h
10e,h
0
0 Unstable
(reactive)
4
3
2
1
H-1
H-1 or
H-2
H-3
H-3
1e,h
5d,e
50d,e
125d,e
(1)e,h
(5)d,e
(50)d,e
(125)d,e
10d,h
50d,e
250d,e
750d,e
¼h
1d
50d
125f
(¼h)
(1)d
(50)d
(125)f
2e,h
10d,e
250d,e
750d,e
¼h
1d
10d
25f
(¼h)
(1)d
(10)d
(25)f
Water
reactive
3
2
H-3
H-3
5d,e
50d,e
(5)d,e
(50)d,e NA
5d
50d
(5)d
(50)d NA
1d
10d
(1)d
(10)d
Note a. For use of control areas, see 780 CMR 417.2
Note b. The aggregate quantity in utilization and storage shall not exceed the quantity listed for storage.
Note c. The quantities of alcoholic beverages in retail sales occupancies shall not be limited provided the
liquids are packaged in individual containers not exceeding 1 gallon. In retail sales and storage
occupancies, the quantities of medicines, foodstuffs and cosmetics, containing not more than 50% by
volume of water-miscible liquids and with the remainder of the solutions not being flammable, shall not be
limited provided that such materials are packaged in individual containers not exceeding one gallon.
Note d. Maximum quantities shall be increased 100% in buildings equipped throughout with an automatic
sprinkler system in accordance with 780 CMR 906.2.1. Where note e. Also applies, the increase for both
notes shall be applied accumulatively.
Note e. Quantities shall be increased 100% when stored in approved cabinets, gas cabinets, fume hoods,
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
USE OR OCCUPANCY
2/7/97 (Effective 2/28/97) 780 CMR - Sixth Edition 61
exhausted enclosures, or safety cans as specified in the fire prevention code listed in Appendix A. Where
note d. also applies, the increase for both notes shall be applied accumulatively.
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
THE MASSACHUSETTS STATE BUILDING CODE
62 780 CMR - Sixth Edition 9/9/05 (Effective 8/26/05)
Note f. The permitted quantities shall not be limited in a building equipped throughout with an automatic
sprinkler system in accordance with 780 CMR 906.2.1.
Note g. A dust explosion potential is considered to exist where 1 pound or more of combustible dust per
1,000 cubic feet of volume is normally in suspension or could be put into suspension in all or a portion of an
enclosure or inside pieces of equipment. This also includes combustible dust which accumulates on
horizontal surface inside buildings or equipment and which could be put into suspension be an accident,
sudden force or sudden explosion.
Note h. Permitted only in buildings equipped throughout with an automatic sprinkler system in accordance
with 780 CMR 906.2.1.
Note i. One pound of black sporting powder and 20 pounds of smokeless powder are permitted in
sprinklered or unsprinklered buildings.
Note j. Containing not more than the exempt amounts of Class I-A, Class I-B or Class I-C flammable
liquids.
Note k. Quantities in parenthesis indicate quantity units in parenthesis at the head of each column. 1
cubic foot = 0.028 m ; 1 pound = 0.454 kg; 1 gallon = 0.00379 m33
Table 307.8(2)
EXEMPT AMOUNTS OF HAZARDOUS MATERIALS, LIQUIDS AND CHEMICALS
PRESENTING A HEALTH HAZARD
MAXIMUM QUANTITIES PER CONTROL AREAa,b,h
Storagec
Closed systemsc
Open systemsc
Material
Solid
poundsd,e
Liquid
gallons
(pounds)d,e
Gas cubic
feet
Solid
poundsd
Liquid
gallons
(pounds)d
Gas cubic
feet
Solid
poundsd
Liquid
gallons
(pounds)d
Corrosive
5,000
500
810d,e
5,000
500
810d,e
1,000
100
Highly toxic
1
(1)
20f
1
(1)
20f ¼
(¼)
Irritant
5,000
500
810d,e
5,000
500
810d,e
1,000
100
Radioactiveg
25 rem - unsealed source
100 rem - sealed source
100 rem - sealed source
25 rem - sealed source
Sensitizer
5,000
500
810d,e
5,000
500
810d,e
1,000
100
Toxic
500
(500)
810d,e
500
(500)
810d,e
125
(125)
Other health
hazards
5,000
500
810d,e
5,000
500
810d,e
1,000
100
Note a. For use of control areas, see 780 CMR 417.2
Note b. In retail sales occupancies, the quantities of medicines, foodstuffs and cosmetics, containing not
more than 50% by volume of water-miscible liquids and with the remainder of the solutions not being
flammable, shall not be limited provided that such materials are packaged in individual containers not
exceeding 1 gallon.
Note c. The aggregate quantity in utilization and storage shall not exceed the quantity listed for storage.
Note d. Maximum quantities shall be increased 100% in buildings equipped throughout with an automatic
sprinkler system in accordance with 780 CMR 906.2.1. Where note e. also applies, the increase for both
notes shall be applied accumulatively.
Note e. Maximum quantities shall be increased 100% when stored in approved storage cabinets, gas
cabinets, fume hoods, exhausted enclosures, or safety cans as specified in the fire prevention code listed in
Appendix A. Where note d. also applies, the increase for both notes shall be applies accumulatively.
Note f. Permitted only when stored in approved exhausted gas cabinets, exhausted enclosures or fume
hoods.
Note g. Maximum dosage permitted in any single exposure.
Note h. Quantities in parenthesis indicate quantity units in parenthesis at the head of each column. 1
cubic foot = 0.028 m ; 1 pound = 0.454 kg; 1 gallon = 0.00379 m33
308.4.4 Occupancy Condition IV: This
occupancy condition shall include all buildings in
which free movement is restricted from an occu-
pied space. Remote-controlled release is provided
to permit movement from all sleeping rooms,
activity spaces and other occupied areas within the
smoke compartment to other smoke compartments.
308.4.5 Occupancy Condition V: This
occupancy condition shall include all buildings in
which free movement is restricted from an
occupied space. Staff-controlled release is
provided to permit movement from all sleeping
rooms, activity spaces and other occupied areas
within the smoke compartment to other smoke
compartments.
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
USE OR OCCUPANCY
2/7/97 (Effective 2/28/97) 780 CMR - Sixth Edition 63
780 CMR 309.0 MERCANTILE USE
GROUP
309.1 General: All buildings and structures which
are occupied for display and sales purposes
involving stocks of goods, wares or merchandise
incidental to such purposes and open to the public,
shall be classified as Use Group M. This includes,
among others, retail stores, automotive service
stations, shops, salesrooms and markets. An
automotive service station is that portion of a
property where motor fuels are stored and dispensed
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
THE MASSACHUSETTS STATE BUILDING CODE
64 780 CMR - Sixth Edition 9/9/05 (Effective 8/26/05)
from fixed equipment into the fuel tanks of motor
vehicles or approved containers, including any
building used for the sale of automotive accessories,
or for minor automotive repair work. Minor repairs
include the exchange of parts, oil changes, engine
tune-ups and similar routine maintenance work.
Retail sales of hazardous materials shall comply
with 780 CMR 307.8 or 780 CMR 426, as
applicable.
780 CMR 310.0 RESIDENTIAL USE
GROUPS
310.1 General: All structures in which individuals
live, or in which sleeping accommodations are
provided (with or without dining facilities),
excluding those that are classified as institutional
occupancies, shall be classified as Use Group R-1,
R-2, R-3, R-4 or R-5. The term "Use Group R" shall
include Use Groups R-1, R-2 and R-3, R-4 and R-5.
Note: Assisted Living Residences which are
certified as such by the Executive Office of Elder
Affairs pursuant to M.G.L. c. 19D shall be
classified in the residential use group R-1, R-2,
R-3 or R-4 as applicable. Portions of an assisted
Living Residence which are used for any use
other than residential shall be classified in
accordance with the intended use.
310.2 Definitions: The following words and terms
shall, for the purposes of 780 CMR 3 and as used
elsewhere in 780 CMR, have the meanings shown
herein.
Dwellings:
Assisted Living Residence: A residence licensed
by the Executive Office of Elder Affairs pursuant
to M.G.L. c. 19D.
Boarding house: A building arranged or used for
lodging for compensation, with or without meals,
and not occupied as a single unit.
Dormitory: A space in a building where group
sleeping accommodations are provided in one
room, or in a series of closely associated rooms.
Dwelling unit: A single unit providing complete,
independent living facilities for one or more
persons, including permanent provisions for
living, sleeping, eating, cooking and sanitation.
Hotel: Any building containing six or more guest
rooms, intended or designed to be used, or which
are used, rented or hired out to be occupied or
which are occupied for sleeping purposes by
guests.
Lodging house: Refer to M.G.L. c. 140, § 22
Motel: A hotel as defined in 780 CMR.
Multiple dwelling: A building or portion thereof
containing more than two dwelling units and not
meeting the requirements for a multiple single
dwelling.
Multiple single dwelling: A building or portion
thereof containing more than two dwelling units
(see 780 CMR 310.5)
One-family dwelling: A building containing one
dwelling unit but not a lodging house (see M.G.L.
c. 140, § 22).
Two-family dwelling: A building containing two
dwelling units but not lodging house (see M.G.L.
c. 140, § 22).
310.3 Use Group R-1 structures: This use group
shall include all hotels, motels, boarding houses and
similar buildings arranged for shelter and sleeping
accommodations and in which the occupants are
primarily transient in nature, occupying the facilities
for a period of less than 30 days.
310.4 Use Group R-2 structures: This use group
shall include all multiple dwellings having more than
two dwelling units, except as provided for in
780 CMR 310.5 for multiple single dwelling units,
and shall also include all boarding houses and
similar buildings arranged for shelter and sleeping
accommodations in which the occupants are
primarily not transient in nature.
310.4.1 Dormitories: A dormitory facility which
accommodates more than five persons more than
2½ years of age shall be classified as Use Group
R-2.
310.5 Use Group R-3 structures: This use group
shall include all buildings arranged for occupancy as
one- or two-family dwellings, including multiple
single family dwellings where each unit has two
independent means of egress not common to any
other dwelling unit, and where each dwelling unit is
separated from adjoining dwelling units by two-hour
fire separation assemblies (see 780 CMR 709.0).
Use group R-3 structures are not lodging houses (see
M.G.L. c. 140, § 22).
Exceptions
1. In multiple single-family dwellings that are
equipped throughout with an approved
automatic sprinkler system installed in
accordance with 780 CMR 906.2.1 or 906.2.2,
the fireresistance rating of the dwelling unit
separation shall not be less than one hour.
Dwelling unit separation walls shall be
constructed as fire partitions (see 780 CMR
711.0).
2. In multiple single-family dwellings that are
equipped throughout with an approved
automatic sprinkler system installed in
accordance with 780 CMR 906.2.3, a two-hour
fire separation assembly shall be provided
between each pair of dwelling units. The
fireresistance rating between each dwelling unit
shall not be less than one hour and shall be
constructed as a fire partition.
310.5.1Family day-care home: A family day-
care home as defined by M.G.L. c.28A, §. 9, shall
be classified as use group R-3 or R-4. Such
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
USE OR OCCUPANCY
2/7/97 (Effective 2/28/97) 780 CMR - Sixth Edition 65
facility shall not accommodate more than six children.
310.6 Use Group R-4 structures: This use group
shall include all detached one- or two-family
dwellings not more than three stories in height, and
the accessory structures.. All such structures shall
be designed in accordance with 780 CMR 36 or in
accordance with the requirements of 780 CMR
applicable to Use Group R-3.
310.7 Use Group R-5 structures: This use group
shall include all buildings arranged for use as
limited group residences in accordance with the
requirements of 780 CMR (see 780 CMR 4).
780 CMR 311.0 STORAGE USE GROUPS
311.1 General: All structures which are primarily
used for the storage of goods, wares or merchandise
shall be classified as Use Group S-1 or S-2. This
includes, among others, warehouses, storehouses and
freight depots. The quantity of hazardous materials
in storage shall comply with 780 CMR 307.8. The
term "Use Group S" shall include Use Groups S-1
and S-2.
311.2 Moderate-hazard storage, Use Group S-1:
Buildings occupied for the storage of moderate-
hazard contents which are likely to burn with
moderate rapidity, but which do not produce either
poisonous gases, fumes or explosives including,
among others, the materials listed in Table 311.2,
shall be classified as Use Group S-1. A motor
vehicle repair garage is that portion of a property
wherein major repairs, such as engine overhauls,
painting or body work, are performed on motorized
vehicles.
Table 311.2
MODERATE-HAZARD STORAGE
OCCUPANCIES
Bags, cloth, burlap and paper
Bamboo and rattan
Baskets
Belting, canvas and leather
Books and papers in rolls and
packs
Boots and shoes
Buttons, including cloth
covered, pearl or bone
Cardboard and cardboard
boxes
Clothing, woolen wearing
apparel
Cordage
Furniture
Furs
Glue, mucilage, paste and size
Horn and combs, other than
celluloid
Leather, enameling or
japanning
Linoleum
Livestock shelters
Lumber yards
Motor vehicle repair garages
Petroleum warehouses for
storage of lubricating
oils with a flash point of
200°F or higher
Photo engraving
Public garages (Group 1) and
stables
Silk
Soap
Sugar
Tobacco, cigars, cigarettes
and snuff
Upholstering and mattress
manufacturing
Wax candles
311.3 Low-hazard storage, Use Group S-2: Low-
hazard storage occupancies shall include buildings
occupied for the storage of noncombustible
materials, and of low-hazard wares that do not
ordinarily burn rapidly such as products on wood
pallets or in paper cartons without significant
amounts of combustible wrappings, but with a
negligible amount of plastic trim such as knobs,
handles or film wrapping. Such occupancies shall be
classified as Use Group S-2 including, among
others, the materials listed in Table 311.3.
Table 311.3
LOW-HAZARD STORAGE OCCUPANCIES
Asbestos
Beer or wine up to 12%
alcohol in metal, glass or
ceramic containers
Cement in bags
Chalk and crayons
Dairy products in nonwaxed
coated paper containers
Dry cell batteries
Electrical coils
Electrical motors
Food products
Foods in noncombustible
containers
Fresh fruits and vegetables in
nonplastic trays or
containers
Frozen foods
Glass
Glass bottles, empty or filled
with noncombustible
liquids
Gypsum board
Inert pigments
Ivory
Meats
Metal cabinets
Metal desks with plastic tops
and trim
Metal parts
Metals
Mirrors
New empty cans
Oil filled and other types of
distribution transformers
Open parking structures
Porcelain and pottery
Public garages (Group 2)
Stoves
Talc and soapstone
Washers and dryers
780 CMR 312.0 UTILITY AND
MISCELLANEOUS USE GROUP
312.1 General: Buildings and structures of an
accessory character and miscellaneous structures not
classified in any specific use group shall be
constructed, equipped and maintained to conform to
the requirements of 780 CMR commensurate with
the fire and life hazard incidental to their occupancy.
Use Group U shall include fences over six feet (1829
mm) high, tanks, cooling towers, retaining walls and
buildings such as private garages, carports, sheds
and agricultural buildings.
780 CMR 313.0 MIXED USE GROUPS
313.1 Two or more use groups: Where a building is
occupied by two or more occupancies not included
in the same use group, the building or portion
thereof shall comply with 780 CMR 313.1.1, 313.1.2
or 313.1.3 or with combinations of 780 CMR
313.1.1, 313.1.2 and 313.1.3, except that
occupancies in Use Group H shall be separated from
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
THE MASSACHUSETTS STATE BUILDING CODE
66 780 CMR - Sixth Edition 9/9/05 (Effective 8/26/05)
all other use groups in accordance with 780 CMR
313.1.2 or 313.1.3. Buildings that include an open
parking structure located beneath an A, I, B, M or R
Use Group shall comply with 780 CMR 313.1.1,
313.1.2, 313.1.3 or 313.2.
Exception: fire areas of Use Group H-1 shall be
in separate and detached buildings and structures
in accordance with 780 CMR 707.1.1.
313.1.1 Nonseparated use groups: Each portion
of the building shall be individually classified as
to use. The required type of construction for the
building shall be determined by applying the
height and area limitations for each of the
applicable use groups to the entire building. The
most restrictive type of construction, so
determined, shall apply. The other requirements
of 780 CMR shall apply to each portion of the
building based on the use group of that occupancy
except that the most restrictive applicable
provisions of 780 CMR 403.0 and 780 CMR 9
shall apply to these nonseparated use groups. A
fire separation assembly is not required between
use groups, except as required by other sections of
780 CMR.
313.1.2 Separated use groups: Each portion of
the building shall be individually classified in a
use group and shall be completely separated from
adjacent fire areas by fire separation assemblies
(see 780 CMR 709.0) and floor/ceiling assemblies
(see 780 CMR 713.0) having a fireresistance
rating determined in accordance with Table
313.1.2, for the use groups being separated. Each
fire area shall comply with the code based on the
use group of that space. Each fire area shall
comply with the height limitations of 780 CMR
503.0 based on the use of that space and the type
of construction classification. In each story, the
building area shall be such that the sum of the
ratios of the floor area of each use group divided
by the allowable area from 780 CMR 503.0 for
each use group shall not exceed one.
Exception: Where the building is equipped
throughout with an automatic sprinkler system
in accordance with 780 CMR 906.2.1, the
required fireresistance rating of fire separation
assemblies separating areas of other than Use
Group H, shall be reduced from those indicated
in Table 313.1.2 by one hour but to not less than
one hour and to not less than that required by
Table 602 for floor construction.
313.1.3 Separate buildings: Each use group shall
be considered a separate building where each such
use group is completely separated from adjacent
use groups by fire walls having a fireresistance
rating corresponding to that required by Table
602. Each building shall then comply with the
provisions of 780 CMR applicable to the use
group of that building.
313.2 Open parking structures beneath other use
groups: Open parking structures constructed under
Use Groups A, I, B, M and R shall not exceed the
height and area limitations permitted under
780 CMR 406.0. The height and area of the portion
of the building above the open parking structure
shall not exceed the limitations in 780 CMR 503.0
for the upper use group. The height, in both feet and
stories, of the portion of the building above the open
parking structure shall be measured from grade
plane and shall include both the open parking
structure and the portion of the building above the
parking structure.
Fire separation assemblies between the parking
occupancy and the upper occupancy shall
correspond to the required fireresistance rating
prescribed in Table 313.1.2 for the uses involved.
The type of construction shall apply to each
occupancy individually, except that all structural
members-including main bracing within the open
parking structure which is necessary to support the
upper occupancy-shall be protected with the more
restrictive fire resistive assemblies of the
occupancies involved as shown in Table 602. Exit
facilities for the upper occupancy shall conform to
780 CMR 10 and shall be separated from the parking
area by fire separation walls having at least a two-
hour fireresistance rating as required by Table 602
and self-closing doors complying with 780 CMR
716.0. means of egress from the open parking
facility shall comply with 780 CMR 1010.5.
313.3 Use Group R: In buildings of Type 2C, 3B or
5B construction with an occupancy in Use Group R,
the first floor shall not be occupied for Use Groups
B and M, unless the floor/ceiling assembly and the
enclosure walls are protected to afford a one-hour
fireresistance rating and the exits from the residential
floors are separately enclosed in accordance with the
requirements of 780 CMR 10.
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
USE OR OCCUPANCY
2/7/97 (Effective 2/28/97) 780 CMR - Sixth Edition 67
Table 313.1.2
FIRERESISTANCE RATING REQUIREMENTS FOR FIRE SEPARATION
ASSEMBLIES BETWEEN FIRE AREASa
Use Group NP- Not Permitted
NA - Not Applicable
A-1
A-2
A-3
A-4
A-5
B
E
F-1
F-2
H-1
H-2
H-3
H-4
I-1
I-2
I-3
M
R-1
R-2
R-3
S-1
S-2
U
A-1
2
3
2
2
2
2
2
2
2
NP
4
3
2
2
3
3
2
2
2
2
2
2
NA
A-2
3
3
3
3
3
3
3
3
NP
4
3
3
3
3
3
3
3
3
3
3
3
NA
A-3
2
2
2
2
2
2
2
NP
4
3
2
2
3
3
2
2
2
2
2
2
NA
A-4
2
2
2
2
2
2
NP
4
3
2
2
3
3
2
2
2
2
2
2
NA
A-5
NA
2
2
2
2
NP
4
3
2
2
3
3
2
2
2
2
2
2
NA
B
2
2
2
2
NP
4
3
2
2
3
3
2
2
2
2
2
2
NA
E
2
2
2
NP
4
3
2
2
3
3
2
2
2
2
2
2
NA
F-1
2
2
NP
4
3
2
2
3
3
2
2
2
2
2
2
NA
F-2
2
NP
4
3
2
2
3
3
2
2
2
2
2
2
NA
U
H-1
NP
NP
NP
NP
NP
NP
NP
NP
NP
NP
NP
NP
NP
NA
S
H-2
4
4
4
4
4
4
4
4
4
4
4
4
NA
E
H-3
3
3
3
3
3
3
3
3
3
3
3
NA
H-4
2
2
2
2
2
2
2
2
2
2
NA
G
I-1
2
3
3
2
2
2
2
2
2
NA
R
I-2
3
3
3
3
3
3
3
3
NA
O
I-3
3
3
3
3
3
3
3
NA
U
M
2
2
2
2
2
2
NA
P
R-1
2
2
2
2
2
NA
R-2
2
2
2
2
NA
R-3
2
2
2
NA
S-1
2
2
NA
S-2
2
NA
U
NA
Note a. Fire resistance ratings are expressed in hours.
780 CMR: STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
THE MASSACHUSETTS STATE BUILDING CODE
68 780 CMR - Sixth Edition 9/9/05 (Effective 8/26/05)
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