DEPARTMENT OF LICENSING AND REGULATORY AFFAIRS  
DIRECTOR’S OFFICE  
CONSTRUCTION CODE  
(By authority conferred on the director of the department of licensing and regulatory affairs by section 4 of  
1972 PA 230, MCL 125.1504, and Executive Reorganization Order Nos. 2003-1, 2008-4 and 2011-4,  
MCL 445.2011, 445.2025 and 445.2030)  
PART 9A. MECHANICAL CODE  
AMENDMENTS AND ADDITIONS TO BASIC MECHANICAL CODE  
R 408.30901 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30901a International mechanical code; adoption by reference.  
Rule 901a. The provisions of the international mechanical code, 2015 edition, except for sections 102.10,  
102.11, 103.2, 103.4, 106.1.1, 106.1.2, 106.5.1 to 106.5.3, 107.2.5 to 107.2.5.3, 109.2 to 109.7, 1101.10,  
and appendix B govern the construction, alteration, relocation, demolition, use, and occupancy of buildings  
and structures. With the exceptions noted, the code is adopted in these rules by reference. All references to  
the International Building Code, International Residential Code, International Energy Conservation Code,  
National Electrical Code, International Mechanical Code, and International Plumbing Code mean the  
Michigan Building Code, Michigan Residential Code, Michigan Energy Code, Michigan Electrical Code,  
Michigan Mechanical Code, and Michigan Plumbing Code respectively. The code is available for  
inspection at the Department of Licensing and Regulatory Affairs, Bureau of Construction Codes, 611 W.  
Ottawa St., 1st Floor Ottawa Building, Lansing, MI 48933. The code may be purchased from the  
time of adoption of these rules of $76.00 each.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS; 2007  
AACS; 2010 AACS.; 2013 AACS; 2016 AACS.  
R 408.30902a Licensing requirements.  
Rule 902a. Section 101.2 of the code is amended to read as follows:  
101.2. Scope. This code regulates 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 the mechanical  
systems, system components, equipment, and appliances specifically addressed in this code.  
Exceptions:  
1. Mechanical systems within 1- and 2-family dwellings shall be constructed and maintained in  
accordance with the Michigan residential code for 1- and 2-family dwellings.  
2. Mechanical systems in existing buildings undergoing repair, alterations, or additions, and  
change of occupancy shall be permitted to comply with the Michigan rehabilitation code for existing  
buildings.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS.  
R 408.30903a Rescinded.  
Page 1  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS.  
R 408.30904a Inspector registration.  
Rule 904a. Section 103.1 of the code is amended to read as follows:  
103.1. General. The position of mechanical inspector is created. The mechanical inspector shall be  
appointed in accordance with 1986 PA 54, MCL 338.2301 et seq.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS.  
R 408.30905a Definitions.  
Rule 905a. The definition of the act is added and the definition of code official is amended to read as  
follows:  
202. "Act" means 1972 PA 230, MCL 125.1501. and known as the Stille-DeRossett-Hale single  
state construction code act.  
"Code official" means a person who is appointed and employed by a governmental subdivision  
who is charged with the administration and enforcement of the state code or codes, and who is  
registered in accordance with 1986 PA 54, MCL 338.2301 to 338.2313.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS ; 2007 AACS.  
R 408.30906 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30906a Work permit; submitting plans and specifications to authority.  
Rule 906a. Sections 106.1, 106.2, 106.3, 106.3.1 106.4, 106.4.3 and 106.4.4 of the code are amended to  
read as follows:  
106.1. Permits required. A contractor licensed under 1984 PA 192, MCL 338.971 to 338.988 who desires  
to erect, install, enlarge, alter, repair, remove, convert, or replace a mechanical system, the installation of  
which is regulated by this code, or to cause such work to be done, shall first make application in accordance  
with the requirements of the act.  
106.2. Permits not required. A person is not required to obtain a permit to perform mechanical work on  
any of the following items:  
(a) A portable heating or gas appliance that has inputs of less than 30,000 Btu’s per hour.  
(b) Portable ventilation appliances and equipment.  
(c) A portable cooling unit.  
(d) Steam, hot water, or chilled water piping within any heating or cooling equipment or appliances  
regulated by the code.  
(e) The replacement of any minor part that does not alter the approval of equipment or an appliance or  
make such equipment or appliance unsafe.  
(f) A portable evaporative cooler.  
(g) Self-contained refrigeration systems that contain 10 pounds or less of refrigerant, or that are actuated  
by motors of 1 horsepower or less.  
(h) Portable fuel cell appliances that are not connected to a fixed piping system and are not  
interconnected to a power grid.  
(i) An oil burner that does not require connection to a flue, such as an oil stove and a heater equipped with  
a wick.  
(j) A portable gas burner that has inputs of less than 30,000 Btu’s per hour.  
(k) When changing or relocating a gas meter or regulator, a permit is not required when installing gas  
piping which shall be limited to 10 feet in length and not more than 6 fittings.  
Page 2  
(l) When installing geothermal vertical closed loops under the supervision of a mechanical contractor  
licensed in HVAC as long as the company meets both the following:  
(1) Has obtained a certificate of registration as a well drilling contractor pursuant to part 127 of the public  
health code.  
(2) Has installed the geothermal vertical closed loops in accordance with the department of environmental  
quality’s best practices regarding geothermal heat pump closed loops.  
Exemption from the permit requirements of this code shall not be deemed to grant authorization for work  
to be done in violation of the provisions of this code or other laws or ordinances of this jurisdiction.  
106.3 Application for permit. Each application for a permit, along with the required fee, shall be filed  
with the code official on a form furnished for that purpose and shall contain a general description of the  
proposed work and its location. The contractor who is performing the work shall sign the application. The  
permit application shall indicate the proposed occupancy of all parts of the building and of that portion of  
the site or lot, if any, not covered by the building or structure and shall contain the information required by  
the act.  
106.3.1 Construction documents. (1) Construction documents, engineering calculations, diagrams, and  
other data shall be submitted in 2 or more sets with each application for a permit. The code official shall  
require construction documents, computations, and specifications to be prepared and designed by a  
registered design professional in accordance with 1980 PA 299, MCL 339.101 to 339.2919.  
Exceptions:  
1. The code official may waive the submission of construction documents, calculations, or other data if  
the nature of the work applied for is such that reviewing of construction documents is not necessary to  
determine compliance with the code.  
2. Construction documents shall not be required when obtaining a permit from the State of Michigan,  
bureau of construction codes for any of the following circumstance:  
a. One-and 2-family dwellings when the heating or cooling input rating is 375,000 Btu’s or less.  
b. Alterations and repair work determined by the mechanical official to be of a minor nature.  
c. Business, mercantile, and storage buildings having HVAC equipment only, with 1 fire area and not  
more than 3,500 square feet.  
d. Work completed by a governmental subdivision or state agency costing less than $15,000.00.  
Bureau code officials may require construction documents in unusual designs and where questions arise as  
a result of a system design beyond conventional system parameters.  
(2) Where special conditions exist, the code official may require additional construction documents to be  
prepared by a registered design professional.  
(3) Construction documents shall be drawn to scale and shall be of sufficient clarity to indicate the  
location, nature, and extent of the work proposed and show in detail that the work conforms to the  
provisions of this code.  
(4) Construction documents for buildings more than 2 stories in height shall indicate where penetrations  
will be made for mechanical systems, and the materials and methods for maintaining required structural  
safety, fire-resistance rating, and fire blocking.  
106.4. Permit issuance. The enforcing agency shall review the application, construction documents, and  
other data filed by an applicant for permit in accordance with the act. If the enforcing agency finds that the  
proposed work conforms to the requirements of the act, the code, and all other applicable laws and  
ordinances thereto, and that all fees prescribed by the act have been paid, then the enforcing agency shall  
issue a permit to the applicant.  
106.4.3. Expiration. Each permit issued by the code official under the provisions of the code shall expire  
by limitation and become null and void if the work authorized by the permit is not begun within 180 days  
from the date of the permit, or if the work authorized by the permit is suspended or abandoned at any time  
after the work is begun for a period of 180 days. Before work is recommenced, the permit shall be  
reinstated if the code has not changed. If the code has changed and the work was not started, a new permit  
shall be first obtained, provided no changes have been made or will be made in the original construction  
document and that suspension or abandonment has not exceeded 1 year.  
106.4.4. Extensions. A permittee holding an unexpired permit may apply for an extension of the time  
within which the permittee may begin work under that permit if for good and satisfactory reasons. The  
code official shall extend the time for action by the permittee for a period not exceeding 180 days if there is  
reasonable cause. No permit shall be extended more than once.  
Page 3  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS; 2007 AACS; 2010  
AACS; 2013 AACS.  
R 408.30907 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30907a Fees.  
Rule 907a. Section 106.5 of the code is amended to read as follows:  
106.5. Fees. The fees prescribed by the act shall be paid to the enforcing agency of the jurisdiction  
before a permit to begin work for new construction, alteration, removal, demolition, or other building  
operation may be issued. In addition, an amendment to a permit necessitating an additional fee shall  
not be approved until the additional fee is paid.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS; 2007 AACS.  
R 408.30908 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30908a Means of appeal.  
Rule 908a. Section 109.1 of the code is amended to read as follows:  
109.1. Means of appeal. An interested person may appeal a decision of the enforcing agency to the board  
of appeals in accordance with the act. An application for appeal shall be based on a claim that the true  
intent of the code or the rules governing construction have been incorrectly interpreted, the provisions of  
the code do not apply, or an equal or better form of construction is proposed. The decision of a local  
board of appeals may be appealed to the Construction Code Commission in accordance with the act and  
the applicable time frames.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS; 2007  
AACS.  
R 408.30909 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30909a Violations.  
Rule 909a. Section 108.4 of the code is amended to read as follows:  
108.4 Violation penalties. Any person who violates a provision of this code, who fails to conform with  
any of the requirements thereof, or who erects, installs, alters, or repairs mechanical work in violation  
of the approved construction documents or directive of the enforcing agency, or a permit or certificate  
issued under the provisions of this code, shall be fined in accordance with the act.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS; 2007 AACS.  
R 408.30910 Rescinded.  
History: 1979 AC; 1989 AACS.  
Page 4  
R 408.30910a Stop work orders.  
Rule 910a. Section 108.5 of the code is amended to read as follows:  
108.5. Stop work orders. Notice shall be in accordance with the act. A person who is served with a stop  
work order, except for work that a person is directed to perform to remove a violation or unsafe condition,  
is subject to the penalty provisions prescribed by the act.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS; 2007 AACS; 2013  
AACS.  
R 408.30911 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30912 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30912a Enclosed parking garages.  
Rule 912a. Section 404.1 of the code is amended to read as follows:  
404.1. Enclosed parking garages. Mechanical ventilation systems for enclosed parking garages are not  
required to operate continuously where the system is arranged to operate automatically upon detection of  
carbon monoxide (CO) not to exceed 25 parts per million (ppm) and nitrogen dioxide (NO2) not to exceed  
3 ppm by approved automatic detection devices.  
404.1.1 Testing. Testing of detection devices shall be per manufacturer’s installation instructions. All  
detectors shall be calibrated per the manufacturer’s instructions at an interval not to exceed 1 year.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 2007 AACS; 2010 AACS; 2013 AACS; 2016 AACS.  
R 408.30913 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30914 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30915 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30915a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2007 AACS; 2010  
AACS; 2013 AACS; 2016 AACS.  
R 408.30916 Rescinded.  
Page 5  
History: 1979 AC; 1989 AACS; 2010 AACS; 2016 AACS.  
R 408.30916a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS.  
R 408.30917 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30917a Rescinded.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30918 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30918a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS; 2007  
AACS; 2010 AACS; 2013 AACS; 2016 AACS.  
R 408.30919 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30919a Rescinded.  
History: 1989 AACS; 1995 AACS.  
R 408.30920 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30920a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; rescinded 1998-2000 AACS.  
R 408.30920 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30921a Rescinded.  
Page 6  
History: 1992 AACS; 1995 AACS.  
R 408.30922 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30922a Rescinded.  
History: 1996 AACS; 1998-2000 AACS.  
R 408.30923 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30923a Equipment installation.  
Rule 923a. Sections 301.10.1 is added to the code and section 309.1 of the code is amended to read as  
follows:  
301.10.1. Electrical disconnect. The mechanical contractor shall ensure that all equipment have an  
electrical disconnect switch on, or immediately adjacent to, the equipment.  
309.1. Occupiable space heating system. Interior spaces intended for human occupancy shall be provided  
with heating facilities capable of maintaining a minimum room temperature of 68 degrees Fahrenheit at a  
point 3 feet above the floor and 2 feet from exterior walls at the design temperature. The installation of  
portable space heaters shall not be used to achieve compliance with this section.  
Exception:  
1. Interior spaces where the primary purpose is not associated with human comfort.  
2. Group F, H, S, and U occupancies.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS; 2010  
AACS; 2013 AACS; 2016 AACS.  
R 408.30924 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30924a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS.  
R 408.30925 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30925a Rescinded.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30926 Rescinded.  
Page 7  
History: 1979 AC; 1989 AACS.  
R 408.30926a Rescinded.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30927 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30927a Equipment and appliances on roofs or elevated structures.  
Rule 927a. Section 306.5 of the code is amended to read as follows:  
306.5 Equipment and appliances on roofs or elevated structures. Where equipment or appliances  
requiring access are located on an elevated structure or the roof of a building so that personnel will have to  
climb higher than 16 feet above grade to access this equipment or appliances, an interior or exterior means  
of access shall be provided. Such access shall not require climbing over obstructions greater than 30 inches  
high or walking on roofs having a slope greater than 4 units vertical in 12 units horizontal (33-percent  
slope). Such access shall not require the use of portable ladders. Where access involves climbing over  
parapet walls, the height shall be measured to the top of the parapet wall.  
Permanent ladders installed to provide the required access shall comply with all of the following  
minimum design criteria:  
(1) The side railing shall extend above the parapet or roof edge not less than 30 inches.  
(2) Ladders shall have rung spacing not to exceed 14 inches on center. The uppermost rung shall be a  
maximum of 24 inches below the upper edge of the roof hatch, roof, or parapet, as applicable.  
(3) Ladders shall have a toe spacing not less than 6 inches deep.  
(4) There shall be a minimum of 18 inches between rails.  
(5) Rungs shall have a minimum 0.75-inch diameter and be capable of withstanding a 300-pound load.  
(6) Ladders over 30 feet in height shall be provided with offset sections and landings capable of  
withstanding 100 pounds per square foot. Landing dimensions shall be not less than 18 inches and not less  
than the width of the ladder served. A guard rail shall be provided on all open sides of the landing.  
(7) Climbing clearance. The distance from the center line of the rungs to the nearest permanent object on  
the climbing side of the ladder shall be a minimum of 30 inches measured perpendicular to the rungs. This  
distance shall be maintained from the point of ladder access to the bottom of the roof hatch. A minimum  
clear width of 15 inches shall be provided on both sides of the ladder measured from the midpoint of and  
parallel with the rungs, except where cages or wells are installed.  
(8) Landing required. A ladder shall be provided with a clear and unobstructed bottom landing area  
having a minimum dimension of 30 inches by 30 inches centered in front of the ladder.  
(9) Ladders shall be protected against corrosion by approved means.  
(10) Access to ladders shall be provided at all times.  
Catwalks installed to provide the required access shall be not less than 24 inches wide and shall have  
railings as required for service platforms.  
Exception 1: An approved, permanent building mounted ladder receiver which prevents the ladder from  
sliding sideways off the building or slipping backward and meets the ladder safety standard of OSHA  
regulations (Standard - 29 CFR) Ladders. - 1926.1053 (b)(1) may be installed on buildings under 20 feet in  
height above grade to access such equipment or appliances.  
Exception 2: This section shall not apply to group R-3 occupancies.  
306.5.1 Sloped roofs. Where appliances are installed on a roof having a slope of 3 units vertical in 12  
units horizontal or greater and having an edge more than 30 inches above grade at such edge, a level  
platform shall be provided on each side of the appliance to which the access is required for service, repair,  
or maintenance. The platform shall not be less than 30 inches in any dimension and shall be provided with  
guards. The guards shall extend not less than 42 inches above the platform, shall be constructed so as to  
prevent the passage of a 21-inch-diameter sphere, and shall comply with the loading requirements for  
Page 8  
guards specified in the Michigan building code. Access to appliances shall not require climbing over  
obstructions greater than 30 inches high or walking on roofs having a slope greater than 4 units vertical in  
12 units horizontal permanent ladders, or equivalent, shall be provided on both sides requiring access in  
accordance with the ladder requirements of section 306.5.  
Exception: This section shall not apply to group R-3 occupancies.  
History: 1989 AACS; 1995 AACS; 2007 AACS; 2010 AACS; 2013 AACS.  
R 408.30928 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30928a Solid fuel burning equipment.  
Rule 928a. Sections 901.5, 929.0, and 929.1 are added to the code to read as follows:  
901.5 Solid fuel burning equipment. Solid fuel burning equipment shall be listed and labeled in  
accordance with section 301.4 of the code and installed in accordance with the manufacturer’s instructions  
and NFPA 211-2013 requirements.  
929.0 Solid fuel hydronic heaters.  
929.1 Solid fuel hydronic heaters shall be listed and labeled, or approved by the code official in  
accordance with the Michigan mechanical code section 105, or have certificate of acceptability issued by  
the Michigan construction code commission.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2010 AACS; 2013  
AACS; 2016 AACS.  
R 408.30929 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30929a Rescinded.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30930 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30930a Rescinded.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30931 Rescinded.  
History: 1979 AC; 1989 AACS; 1998-2000 AACS.  
R 408.30931a Rescinded.  
Page 9  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30931b Rescinded.  
History: 1979 AC; 1989 AACS; 1998-2000 AACS.  
R 408.30932a Rescinded.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30933 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30933a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30934 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30935 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30935a Commercial kitchens; ventilation.  
Rule 935a Sections 506.1, 506.3.6, 507.1, and 507.2.6, of the code are amended and sections 507.16.1.1  
is added to the code to read as follows:  
506.1. Ventilation requirements for commercial kitchens. Commercial kitchen hood ventilation ducts and  
exhaust equipment shall be in compliance with NFPA-96-2014, which is the standard of the national fire  
protection association listed in chapter 15 of the code.  
506.3.6 Grease duct clearances. Grease duct systems and exhaust equipment serving a type I hood shall  
have clearances to combustibles as required by NFPA-96-2014, as listed in chapter 15 of the code.  
Exception: Listed and labeled factory-built commercial kitchen grease ducts and exhaust equipment  
installed in accordance with section 304.1 of the code.  
507.1 General. Commercial kitchen exhaust hoods shall comply with the requirements of this subrule  
and NFPA 96-2014. Hoods shall be type I or type II and shall be designed to capture and confine cooking  
vapors and residues. A type I or type II hood shall be installed at or above all commercial cooking  
appliances in accordance with sections 507.2 and 507.3 of the code. When a cooking appliance under a  
single hood requires a type I hood, a type I hood shall be installed. When a type II hood is required, a type  
I or type II hood shall be installed. When a type I hood is installed, the installation of the entire system,  
including the hood, ducts, exhaust equipment, and makeup air system, shall comply with the requirements  
of sections 506, 507, 508, and 509 of the code.  
Exceptions:  
1. Factory-built commercial exhaust hoods that are listed and labeled in accordance with UL 710, and  
installed in accordance with section 304.1 of the code, shall not be required to comply with sections  
507.1.5, 507.2.3, 507.2.5, 507.2.8, 507.3.1, 507.3.3, 507.4, and 507.5 of the code.  
Page 10  
2. Factory-built commercial cooking recirculating systems that are listed and labeled in accordance with  
UL 710B and installed in accordance with section 304.1 of the code, shall not be required to comply with  
sections 507.1.5, 507.2.3, 507.2.5, 507.2.8, 507.3.1, 507.3.3, 507.4, and 507.5 of the code. Spaces in which  
these systems are located shall be considered kitchens and shall be ventilated in accordance with table  
403.3.1.1. For the purpose of determining the floor area required to be ventilated, each appliance shall be  
considered as occupying not less than 100 square feet (9.3 m2).  
3. When cooking appliances are equipped with integral down-draft exhaust systems and these appliances  
and exhaust systems are listed and labeled for the application in accordance with NFPA 96-2014, a hood  
shall not be required at or above these appliances.  
507.2.6. Clearances for type I hood. A type I hood shall be installed with clearances from combustibles  
as required by NFPA-96-2014 as listed in chapter 15 of the code.  
507.16.1.1 Smoke test. The field test identified in section 507.16.1 of the code shall be conducted in  
accordance with the smoke testing procedures established by the bureau of construction codes, which are  
of Licensing and Regulatory Affairs, Bureau of Construction Codes, 611 W. Ottawa St., 1st Floor Ottawa  
Building, Lansing, MI 48933.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS; 2007  
AACS; 2010 AACS; 2013 AACS; 2016 AACS.  
R 408.30936 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30936a Scope of article.  
Rule 936a. Section 1001.2 is added to the code and section 1004.3 of the code is amended to read as  
follows:  
1001.2. Boilers. In addition to the other provisions of the code, this article governs the installation,  
alteration, and repair of water heaters and boilers. The installation of boilers shall be in compliance with  
the provisions of this code and the Michigan boiler code.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS; 2007  
AACS; 2016 AACS.  
R 408.30937 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30937a Rescinded.  
History: 1989 AACS; 1995 AACS; rescinded 1998-2000 AACS.  
R 408.30938 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30938a Rescinded.  
History: 1989 AACS; 1995 AACS.  
Page 11  
R 408.30939 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30940 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30940a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS.  
R 408.30941 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30941a Rescinded.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30942 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30942a Rescinded.  
History: 1989 AACS; 1995 AACS.  
R 408.30943 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30943a Rescinded.  
History: 1989 AACS; 1995 AACS.  
R 408.30944 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30944a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS.  
Page 12  
R 408.30945 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30945a Ventilation; exhaust.  
Rule 945a. Sections 501.3, 504.4, 504.8.2, 504.10, and 505.3 of the code are amended to read as follows:  
501.3 Exhaust discharge. The air removed by every mechanical exhaust system shall be discharged  
outdoors at a point where it will not cause a public nuisance and not less than the distances specified in  
section 501.3.1 of the code. The air shall be discharged to a location from which it cannot again be readily  
drawn in by a ventilating system. Air shall not be exhausted into an attic or a crawl space, be directed onto  
walkways, or terminate within 3 feet of a ventilated section in a soffit.  
Exceptions:  
1. Whole-house ventilation-type attic fans shall be permitted to discharge into the attic space of dwelling  
units that have private attics.  
2. Commercial cooking recirculating systems.  
3. When installed in accordance with the manufacturer’s instructions and when mechanical or natural  
ventilation is otherwise provided in accordance with chapter 4 of the code, listed and labeled domestic  
ductless range hoods shall not be required to discharge to the outdoors.  
504.4 Exhaust installation. Dryer exhaust ducts for clothes dryers shall terminate on the outside of the  
building, shall not terminate within 3 feet of a ventilated section in a soffit, and shall be equipped with a  
back draft damper. Screens shall not be installed at the duct termination. Ducts shall not be connected or  
installed with sheet metal screws or other fasteners that will obstruct the exhaust flow. Clothes dryer  
exhaust ducts shall not be connected to a vent connector, vent, or chimney. Clothes dryer exhaust ducts  
shall not extend into or pass through ducts or plenums.  
504.8.2 Duct installation. Dryer exhaust ducts shall be supported at 4 foot (1,219 mm) intervals and  
secured in place. The insert end of the duct shall extend into the adjoining duct or fitting in the direction of  
airflow. Ducts shall not be joined with screws or similar fasteners that protrude into the inside of the duct.  
504.10 Common exhaust systems for clothes dryers located in multistory structures. When a common  
multistory duct system is designed and installed to convey exhaust from multiple clothes dryers, the system  
shall be engineered by a registered design professional and installed in accordance with the Michigan  
building construction codes.  
505.3 Common exhaust systems for domestic kitchens located in multistory structures. When a common  
multistory duct system is designed and installed to convey exhaust from multiple domestic kitchens, the  
system shall be engineered by a registered design professional and installed in accordance with the  
Michigan building construction codes.  
History: 2003 AACS; 2007 AACS; 2010 AACS; 2013 AACS; 2016 AACS.  
R 408.30946 Alterations and repairs.  
Rule 946. Section 1001.3 is added to the code to read as follows:  
1001.3. Alterations and repairs to boilers shall be in accordance with the Michigan boiler act, 1965 PA  
290, MCL 408.751 to MCL 408.776.  
History: 1979 AC; 1989 AACS; 2010 AACS; 2013 AACS.  
R 408.30946 Alterations and repairs.  
Rule 946. Section 1001.3 is added to the code to read as follows:  
1001.3. Alterations and repairs. Alterations and repairs to boilers shall be in accordance with the  
Michigan boiler act, 1965 PA 290, MCL 408.751 to 408.776.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS; 2010 AACS; 2016 AACS.  
Page 13  
R 408.30947 Rescinded.  
History: 1979 AC; 1989 AACS; 2010 AACS; 2013 AACS; 2016 AACS.  
R 408.30947a Boiler connections.  
Rule 947a. Section 1005.1 of the code is amended to read as follows:  
1005.1 Valves. Every boiler or modular boiler shall have a shutoff valve in the supply and return piping.  
For multiple boiler or multiple modular boiler installations, each boiler or modular boiler shall have  
individual shutoff valves in the supply and return piping.  
Exception: Shutoff valves are not required in a system having a single low-pressure steam boiler. When a  
boiler is located above the system and can be drained without draining the system, stop valves may be  
eliminated.  
History: 2013 AACS.  
R 408.30948 Boiler safety devices.  
Rule 948. Section 1006.1.1 is added to the code and 1006.7 of the code is amended to read as follows:  
1006.1.1 Safety and safety relief inlets. The opening or connection between the boiler and any safety or  
safety relief valve shall have at least the area of the valve inlet.  
1006.7. Boiler safety devices. Boilers shall be equipped with controls and limit devices as required by  
ASME, CSD-1-2012, the manufacturer’s installation instructions, and the conditions of the listing. All  
controls and safety devices shall be tested and maintained in accordance with ASME code CSD-1-2012.  
History: 1979 AC; 1989 AACS; 2010 AACS; 2013 AACS; 2016 AACS.  
R 408.30948a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2013 AACS; 2016 AACS.  
R 408.30949 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30949a Rescinded.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30950 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30951 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30951a Rescinded.  
Page 14  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30952 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30952a Rescinded.  
History: 1989 AACS; 1995 AACS.  
R 408.30953a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30954 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30954a Rescinded.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30955 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30955a Rescinded.  
History: 1989 AACS; 1992 AACS.  
R 408.30956 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30956a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30957 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30958 Rescinded.  
History: 1979 AC; 1989 AACS.  
Page 15  
R 408.30958a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30959 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30960a Rescinded.  
History: 1989 AACS; 1992 AACS.  
R 408.30962 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30962a Rescinded.  
History: 1996 AACS; 1998-2000 AACS.  
R 408.30963a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30964 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30964a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS.  
R 408.30965 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30965a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30966 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30966a Rescinded.  
Page 16  
History: 1989 AACS; 1992 AACS.  
R 408.30967 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30967a Rescinded.  
History: 1989 AACS; 1992 AACS.  
R 408.30968 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30968a Rescinded.  
History: 1989 AACS; 1992 AACS.  
R 408.30969 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30970a Rescinded.  
History: 1989 AACS; 1992 AACS.  
R 408.30971 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30971a Rescinded.  
History: 1989 AACS; 1992 AACS.  
R 408.30972 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30972a Rescinded.  
History: 1989 AACS; 1992 AACS.  
R 408.30974 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30975a Rescinded.  
Page 17  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30977a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS.  
R 408.30980 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30981 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30982 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30982a Rescinded.  
History: 1992 AACS; 1995 AACS.  
R 408.30983a Rescinded.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30984 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30984a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30986 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30987a Rescinded.  
History: 1989 AACS; 1995 AACS; 1998-2000 AACS.  
R 408.30988 Rescinded.  
History: 1979 AC; 1989 AACS.  
Page 18  
R 408.30989 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30989a Rescinded.  
History: 1989 AACS; 1992 AACS; 1995 AACS.  
R 408.30990 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30992 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30992a Rescinded.  
History: 1989 AACS; 1995 AACS.  
R 408.30993 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30994 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30995 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30995a Automatic sprinkler systems generally.  
Rule 995a. Sections 1600.0, 1600.1, and 1600.2 are added to the code to read as follows:  
1600.0. Automatic sprinkler systems; fire suppression systems.  
1600.1 Scope. The provisions of this article provide the minimum requirements for the design and  
installation of automatic sprinkler systems in all occupancies, except for 1- and 2-family dwellings.  
1600.2. Installations. Installations shall be in compliance with the provisions of the code. Fire  
suppression systems shall be in compliance with the provisions of the building code and shall be installed  
in accordance with the code and NFPA-13-2010, NFPA-13D-2010, NFPA-13R-2010, and NFPA-24-2010,  
installation of sprinkler systems, installation of sprinkler systems in 1- and 2-family dwellings and  
manufactured homes, installation of sprinkler systems in residential occupancies up to 4 stories in height,  
and standards of the national fire protection association listed in chapter 15.  
History: 1989 AACS; 1992 AACS; 1995 AACS; 1998-2000 AACS; 2001 AACS; 2003 AACS; 2007  
AACS; 2010 AACS; 2013 AACS.  
R 408.30996 Process piping.  
Rule 996. Sections 1700.0 and 1700.1 are added to the code to read as follows:  
Page 19  
1700.0. Process piping.  
1700.1 Scope. The provisions of this chapter provide the minimum requirements for the design and  
installation of process piping systems pursuant to ASME B31.3-2010  
1700.2 Process piping. Piping which is not part of a refrigeration system or part of a system designed to  
provide air conditioning. Process piping includes pipes which transfer chemicals and other fluids, gases, or  
vapors for systems other than air conditioning systems as covered by the Michigan mechanical code.  
History: 1979 AC; 1989 AACS; 2013 AACS.  
R 408.30997 Rescinded.  
History: 1979 AC; 1989 AACS.  
R 408.30998 Rescinded.  
History: 1979 AC; 1989 AACS.  
Page 20