Cal. Civ. Code § 110-11-1-.27

GEORGIA STATE MINIMUM STANDARD
MECHANICAL CODE (INTERNATIONAL MECHANICAL CODE WITH GEORGIA STATE
AMENDMENTS)

The INTERNATIONAL MECHANICAL CODE, 2024
Edition, published by the International Code Council, when used in conjunction
with these Georgia State Amendments, shall constitute the official
Georgia State Minimum Standard Mechanical Code.

GEORGIA STATE AMENDMENTS

CODE REFERENCE:

a)

Replace all references to the ICC
Electrical Code with references to the Georgia State
Minimum Standard Electrical Code (National Electrical Code with Georgia State
Amendments).

b)

Replace
all references to the International Energy Conservation Code
(IECC) with references to the Georgia State Minimum Standard
Energy Code (IECC with Georgia State Supplements and Amendments). The
Georgia State Minimum Standard Energy Code shall be used for
efficiency and coefficient of performance ratings of mechanical equipment.
APPENDICES:

Appendices are not enforceable unless they are specifically
referenced in the body of the code or adopted by the Department of Community
Affairs or the Authority Having Jurisdiction.

SCOPE:

The provisions of the Georgia State Minimum Standard
Mechanical Code shall regulate the design, installation, maintenance,
alteration and inspection of mechanical systems that are
permanently installed and utilized to provide control of environmental
conditions and related processes within buildings. This code shall also
regulate those mechanical systems, system components,
equipment and appliances specifically addressed herein. The
installation of fuel gas distribution piping and equipment,
fuel gas-fired appliances and fuel gas-fired appliance venting
system shall be regulated by the Georgia State Minimum Standard Gas
Code (International Fuel Gas Code with Georgia Amendments).

Exception #1: Detached one- and two-family
dwellings and multiple single-family dwellings (townhouses) not more than three
stories above grade with separate means of egress and their accessory
structures shall comply with the Georgia State Minimum Standard One-
and Two-Family Dwellings Code (International Residential Code for One- and Two-
Family Dwellings with Georgia State Amendments).

Exception #2: The following table titled 'Codes
Reference Guide' establishes specific primary and supplementary code
applications and is to be applied by the Authority Having Jurisdiction.

CODES REFERENCE
GUIDE

Area

Primary

Supplement

Occupancy Classification

LSC

IBC

Building Construction Types, including allowable
height, allowable building areas, and the requirements for sprinkler protection
related to minimum building construction types.

IBC

LSC

Means of Egress

LSC

NONE

Standpipes

IBC

IFC

Interior Finish

LSC

NONE

HVAC Systems

IMC

NONE

Vertical Openings

LSC

NONE

Sprinkler Systems minimum construction
standard

LSC

NONE

Fire Alarm Systems

LSC

NONE

Smoke Alarms and Smoke

Detection Systems

State Statute and LSC

NONE

Portable Fire Extinguishers

IFC

NONE

Cooking Equipment

LSC and NFPA 96

NONE

Fuel Fired Appliances

IFGC

NFPA 54

Liquid Petroleum Gas

NFPA 58

NFPA 54

Compressed Natural Gas

NFPA 52

NONE

GEORGIA STATE MINIMUM

REQUIREMENTS FOR BOILERS/WATER HEATERS
AND PRESSURE VESSELS

The State's minimum requirements for boilers/water heaters
and pressure vessels over 200,000 BTU/h (58.61 kW), 210 degrees Fahrenheit or
120 gallons capacity shall be established by O.C.G.A. Title 25, Chapter 15 and
the Rules and Regulations of the Office of Insurance and Safety Fire
Commissioner.

*Revise the International Mechanical Code, 2024
Edition, as follows:

CHAPTER 1

SCOPE AND ADMINISTRATION

*Delete Chapter 1 'Scope and Administration' without
substitution. Chapter 1 to remain in the Code as a reference and guide for
local governments in the development of their own Administrative
Procedures.

(Effective January 1, 2026)

CHAPTER 3

GENERAL REGULATIONS

SECTION 301

GENERAL

*Revise Section 301.1 'Scope' to read as follows:

301.1

Scope. This chapter shall
govern the approval and installation of all equipment and appliances that
comprise parts of the building mechanical systems regulated by this code.
(Effective January 1, 2026)

*Revise Section 301.2 'Energy utilization' to read as
follows:

301.2

Energy
utilization. Heating, ventilating and air-conditioning systems of all
structures shall be designed and installed for efficient utilization of energy
in accordance with the International Energy Conservation Code.
Cooling towers installed in new construction shall be in compliance with
ASHRAE, Standard 90.1.
(Effective January 1, 2026)

*Revise Section 301.7 'Listed and labeled' to read as
follows:

301.7

Listed
and labeled. Appliances regulated by this code shall be
listed and labeled for the application in
which they are installed and used, unless otherwise approved.
Exception to remain unchanged.

(Effective January 1, 2026)

*Add new Section 301.19 'Related fire codes' to read as
follows:

301.19

Related
fire codes. Any reference to the International Fire
Code and/or NFPA standards in any chapter of this code shall be to the
latest edition as adopted and amended by the Georgia Insurance and Safety Fire
Commissioner.
(Effective January 1, 2026)

SECTION 306

ACCESS AND SERVICE SPACE

*Revise Section 306.3 'Appliances in attics' to add new
exception #3 to read as follows:

306.3

Appliances in attics.Exceptions:

3.

In Residential Occupancies, attics
containing appliances or mechanical equipment service shall be accessible by
pull-down stairs or other permanent steps and at a minimum be sized to allow
the removal of the largest appliance.
(Effective January 1, 2026)

CHAPTER 4

VENTILATION

SECTION 401

GENERAL

*Revise section 401.2 'Ventilation required' to read as
follows:

401.2

Ventilation required. Every occupied space shall be ventilated by
natural means in accordance with Section 402 or by mechanical means in
accordance with Section 403. Where the air infiltration rate in a dwelling unit
is less than three air changes per hour when tested with a blower door at a
pressure of 0.2-inch water column (50 Pa) in accordance with the Georgia State
Minimum Standard Energy Code, the dwelling unit shall be ventilated by
mechanical means in accordance with Section 403. Ambulatory care facilities and
Group I-2 occupancies shall be ventilated by mechanical means in accordance
with Section 407.
(Effective January 1, 2026)

*Add new Section 401.7 'Alternative ventilation procedures'
to read as follows:

401.7

Alternative ventilation procedures. As an alternative to Chapter
4, the following shall be permitted:

1.

Ventilation Rate Procedure, Natural Ventilation Procedure or Indoor Air Quality
Procedure, as prescribed by ASHRAE 62.1. Software programs to calculate outdoor
ventilation air may be used to demonstrate ASHRAE 62.1 compliance, as approved
by authority having jurisdiction.

2.

A combination of ASHRAE 62.1 and
ANSI/ASHRAE/ASHE Standard 170 may be utilized for different occupancy types
within a single building.
(Effective January 1, 2026)

CHAPTER 5

EXHAUST SYSTEMS

SECTION 501

GENERAL

*Revise Section 501.3 'Exhaust discharge' Exception #1 to
read as follows:

501.3

Exhaust discharge.Exceptions:

1.

Whole-house ventilation-type attic fans
shall be permitted to discharge into the ventilated attic space of
dwelling units having private attics, provided the installed
system meets paragraph 501.4 requirements for pressure equalization.
(Effective January 1, 2026)

SECTION 505

DOMESTIC COOKING EXHAUST
EQUIPMENT

*Add new Section 505.3.1 'Exhaust ducts for domestic range
hoods installed in commercial applications' to read as follows:

505.3.1

Exhaust
Ducts for domestic range hoods installed in commercial applications.
Exhaust ducts for domestic range hoods installed in commercial applications
including I-1 and I-2 occupancies shall be vented to the outside and shall be
constructed of (a) Type B vent, or (b) smooth wall duct constructed of
galvanized or stainless steel with a minimum duct thickness of 0.0157 inches
(0.40 mm) or constructed of aluminum or copper with a minimum duct thickness of
0.023 inches (0.58mm).
(Effective January 1, 2026)

*Add new Section 505.9 'Commercial installations
of domestic systems' to read as follows:

505.9

Commercial installations of
domestic systems. Commercial installations of domestic systems shall
comply with the current Life Safety Code NFPA 101 and 96 standards as adopted
and amended by the Georgia Insurance and Safety Fire Commissioner.
(Effective January 1, 2026)

SECTION 506

COMMERCIAL KITCHEN HOOD VENTILATION
SYSTEM DUCTS AND EXHAUST EQUIPMENT

*Delete Section 506.1 'General' and substitute the
following:

506.1

General. The State's minimum requirements for Type I commercial
kitchen hood ventilation system ducts and exhaust equipment shall be designed,
constructed and installed in accordance with the Life Safety Code NFPA 101 and
NFPA 96 as adopted and amended by the Georgia Insurance and Safety Fire
Commissioner. Other commercial kitchen hood ventilation system ducts and
exhaust equipment shall comply with the requirements of this section.
(Effective January 1, 2026)

SECTION 507

COMMERCIAL KITCHEN HOODS

*Delete Section 507.1 'General' and substitute the
following:

507.1

General. The State's minimum requirements for Type I commercial
kitchen hoods shall be designed, constructed and installed in accordance with
the Life Safety Code NFPA 101 and NFPA 96 as adopted and amended by the Georgia
Insurance and Safety Fire Commissioner. Other commercial kitchen hoods shall
comply with the requirements of this section.
(Effective January 1, 2026)

*Delete Section 507.1.2 'Domestic cooking
appliances used for commercial purposes' without substitution.

(Effective January 1, 2026)

*Delete Section 507.2.11 'Fire suppression systems' and
substitute the following:

507.2.11

Fire suppression
systems. The State's minimum requirements for fire suppression systems
for commercial cooking equipment shall be established by the Life Safety Code
NFPA 101 and NFPA 96 as adopted and amended by the Georgia Insurance and Safety
Fire Commissioner.
(Effective January 1, 2026)

CHAPTER 6

DUCT SYSTEMS

SECTION 606

SMOKE DETECTION SYSTEMS
CONTROL

*Rename Section 606.2.1 'Return air systems' and
revise to read as follows:

606.2.1

Supply air systems.
Smoke detectors shall be installed in supply air systems with a design capacity
greater than 2,000 cfm (0.9m3/s), in the supply air
duct downstream of any filters, fan motors, outdoor air connections, and
upstream of any branch connections or decontamination equipment and appliances.

Exception: Smoke detectors are not required in
the supply air system where all portions of the building served by the air
distribution system are protected by area smoke detectors connected to a fire
alarm system in accordance with NFPA 72. The area smoke detection system shall
comply with Section 606.4.

(Effective January 1, 2026)

*Revise Section 606.2.2 'Common supply and return air
systems' to read as follows:

606.2.2

Common supply and return air
systems. Where multiple air-handling systems share common supply or
return air ducts or plenums with a combined design capacity greater than 2,000
cfm (0.9m3/s), the supply air system shall be
provided with smoke detectors in accordance with Section 606.2.1.
Exception: Individual smoke detectors shall not
be required for each fan-powered unit, provided that such units do not have an
individual design capacity greater than 2,000 cfm
(0.9m3/s) and will be shut down by activation of one
of the following:

1.

Smoke detectors
required by Sections 606.2.1 and 606.2.3.

2.

An approved area smoke detector system
located in the common plenum(s) serving such units.

3.

An area smoke detector system as
prescribed in the exception to Section 606.2.1.
In all cases, the smoke detectors shall comply with sections
606.4 and 606.4.1.

(Effective January 1, 2026)

*Revise Section 606.4.1 'Supervision' first sentence to read
as follows:

606.4.1

Supervision. The duct
smoke detectors shall be connected to a fire alarm system where a fire alarm
system is required by the Life Safety Code NFPA 101 and NFPA 72 as adopted and
amended by the Georgia Insurance and Safety Fire Commissioner.
(Effective January 1, 2026)

CHAPTER 9

SPECIFIC APPLIANCES, FIREPLACES AND
SOLID FUEL-BURNING EQUIPMENT

SECTION 908

COOLING TOWERS, EVAPORATIVE CONDENSERS
AND FLUID COOLERS

* Revise Section 908.1 'General' to read as
follows:

908.1

General. A cooling tower used in conjunction with an
air-conditioning appliance shall be installed in accordance with the
manufacturer's installation instructions. Factory-built cooling towers shall be
listed in accordance with UL 1995 or UL/CSA 60335-2-40. The standards related
to high efficiency cooling towers shall include without limitation the minimum
standards prescribed by the ASHRAE, Standard 90.1.
(Effective January 1, 2026)

SECTION 917

COOKING APPLIANCES

*Revise Section 917.1 'Cooking appliances' to add new
Exception to read as follows:

Exception:

Listed and labeled
commercial cooking appliances may be installed in dwelling
units and domestic kitchens when such installation is designed by a
Georgia Licensed Professional Engineer and accepted by the local authority
having jurisdiction.

(Effective January 1, 2026)

*Delete Section 917.2 'Domestic appliances' without
substitution.

(Effective January 1, 2026)

CHAPTER 10

BOILERS, WATER HEATERS AND PRESSURE
VESSELS

SECTION 1001

GENERAL

*Revise Section 1001.1 'Scope' to add the following at the
end of the first paragraph:

1001.1

Scope. ...and pressure
vessels. The State's minimum requirements for boilers/water heaters and
pressure vessels over 200,000 BTU/h (58.61 kW), 210 degrees Fahrenheit or 120
gallons capacity shall be established by O.C.G.A. Title 25, Chapter 15 and the
as adopted and amended Rules and Regulations of the Office of Insurance and
Safety Fire Commissioner.
(Effective January 1, 2026)

CHAPTER 11

REFRIGERATION

SECTION 1101

GENERAL

* Delete section 1101.1.1 'Refrigerants other than ammonia'
and substitute the following:

1101.1.1

Refrigerants other than
ammonia. Refrigeration systems using a refrigerant other than ammonia
shall comply with this chapter, the International Fire Code, and either ASHRAE
15 or ASHRAE 15.2, as applicable. Refrigeration systems containing carbon
dioxide as the refrigerant shall also comply with IIAR CO2.
(Effective January 1, 2026)

SECTION 1105

MACHINERY ROOM, GENERAL
REQUIREMENTS

*Renumber Section [F] 1105.3 'Refrigerant
detector' as 1105.3 and revise to read as follows:

1105.3

Refrigerant detector.
Refrigerant detectors in machinery rooms shall be provided as required in
accordance with ASHRAE 15.
(Effective January 1, 2026)

SECTION 1106

MACHINERY ROOM, SPECIAL
REQUIREMENTS

*Renumber Section [F] 1106.5 'Remote controls'
as 1106.5 and revise to read as follows:

1106.5

Remote controls. Remote
control of the mechanical equipment and appliances located in the machinery
room shall be provided as required in accordance with ASHRAE 15.
(Effective January 1, 2026)

*Renumber Section [F] 1106.6 'Emergency signs
and labels' as 1106.6 and revise to read as follows:

1106.6

Emergency signs and
labels. Refrigeration units and systems shall be provided with
approved signs, charts and labels in accordance with ASHRAE
15.
(Effective January 1, 2026)

SECTION 1107

PIPING MATERIAL

*Revise 1107.4 'Piping materials standards' to read as
follows:

1107.4

Piping
materials standards. Refrigerant pipe shall conform to one or more of
the standards listed in Table 1107.4. For refrigeration systems used in
residential occupancies serving only a single dwelling unit or sleeping unit,
refrigerant piping and tubing shall be limited to aluminum, copper, and copper
alloy. The exterior of the pipe shall be protected from corrosion and
degradation.
(Effective January 1, 2026)

*Revise 1107.5 'Pipe fittings' to read as follows:

1107.5

Pipe fittings.
Refrigerant pipe fittings shall be approved for installation with the piping
materials to be installed, and shall conform to one of more of the standards
listed in Table 1107.5 or shall be listed and labeled as complying with UL 207.
For refrigeration systems used in residential occupancies serving only a single
dwelling unit or sleeping unit, refrigerant fittings shall be limited to
aluminum, copper, copper alloys, stainless steel, and steel.
(Effective January 1, 2026)

SECTION 1109

REFRIGERANT PIPE
INSTALLATION

* Revise 1109.3.2 'Shaft ventilation' to read as
follows:

1109.3.2

Shaft
ventilation. Required refrigerant pipe shafts with systems using Group
A2L or B2L refrigerant shall be naturally or mechanically ventilated.
Refrigerant pipe shafts with one or more systems using any Group A2, A3, B2 or
B3 refrigerant shall be continuously mechanically ventilated and shall include
a refrigerant detector. The shaft ventilation exhaust outlet shall comply with
Section 501.3.1. Naturally ventilated shafts shall have a pipe, duct, or
conduit not less than 4 inches (102 mm) in diameter that connects to the lowest
point of the shaft and extends to the outdoors. The pipe, duct or conduit shall
be level or pitched downward to the outdoors.
Mechanically ventilated shafts shall have a minimum airflow
velocity in accordance with Table 1109.3.2. The mechanical ventilation shall be
continuously operated or activated by a refrigerant detector. Systems utilizing
a refrigerant detector shall activate the mechanical ventilation at a maximum
refrigerant concentration of 25 percent of the lower flammable limit of the
refrigerant.

The detector, or a sampling tube that draws air to the
detector, shall be located in an area where refrigerant from a leak will
concentrate. The shaft shall not be required to be ventilated for double-wall
refrigerant pipe where the interstitial space of the double-wall pipe is vented
to the outdoors. For refrigeration systems used in residential occupancies
serving only a single dwelling unit or sleeping unit, shaft ventilation shall
not be required where the pipe or tube is continuous without fittings in the
shaft.

(Effective January 1, 2026)

* Revise section 1109.2.5 'Refrigerant pipe shaft' Exception
1 and 2 to read as follows:

1109.2.5

Refrigerant pipe
shafts. Refrigerant piping that penetrates two or more floor/ceiling
assemblies shall be enclosed in a fire-resistance-rated shaft enclosure. The
fire-resistance-rated shaft enclosure shall comply with Section 713 of the
International Building Code.
Exceptions:

1.

Refrigeration systems
using R-718 refrigerant (water).

2.

Piping in a direct refrigeration system where the refrigerant quantity does not
exceed the limits of Table 1103.1 for the smallest occupied space through which
the piping passes.

3.

Piping
located on the exterior of the building where vented to the
outdoors.
(Effective January 1, 2026)

CHAPTER 13

FUEL OIL PIPING AND
STORAGE

SECTION 1301

GENERAL

*Revise Section 1301.1 'Scope' to add the following at the
end of the paragraph:

1301.1

Scope. ...International
Fire Code. The State's minimum requirements for fuel oil piping and storage
shall be as established by the Georgia State Minimum Fire Safety Standards and
the as adopted and amended Rules and Regulations of the Georgia Insurance and
Safety Fire Commissioner. Any areas not addressed by the Georgia State Minimum
Fire Safety Standards shall be regulated by this chapter.
(Effective January 1, 2026)

CHAPTER 14

SOLAR THERMAL SYTEMS

SECTION 1402

DESIGN AND INSTALLATION

*Revise Section 1402.4 'Protection from freezing' to read as
follows:

1402.4

Protection from freezing. System Components shall be protected
from damage by freezing of heat transfer liquids at the lowest ambient
temperatures that will be encountered. Freeze... (Remainder of paragraph to
remain unchanged)
(Effective January 1, 2026)

SECTION 1403

HEAT TRANSFER FLUIDS

*Add new Section 1403.2.1 'Protection of drains' to read as
follows:

1403.2.1

Protection of drains. Drains serving heat transfer fluids over
140°F (60°C) or which are toxic or corrosive shall be protected in accordance
with the requirements of The International Plumbing Code.
(Effective January 1, 2026)

CHAPTER 15

REFERENCED STANDARDS

*Revise Chapter 15 'Referenced Standards' to add the
following:

ASHRAE

Standard reference number

Title

Referenced in code section number

15.2-2022

Safety Standard for Refrigeration Systems in
Residential Applications

1101.1.1, GA Amendments

(Effective January 1, 2026)