1. 08 MAINE OFFICE OF COMMUNITY AFFAIRS
   1. 003 BUILDING CODES AND STANDARDS

      Chapter 8: MAINE UNIFORM BUILDING AND ENERGY CODE – MECHANICAL CODE (formerly 16-642 C.M.R. Ch. 7)

SUMMARY: This chapter establishes the Mechanical Code component of the Maine Uniform Building and Energy Code “MUBEC”. The provisions of this chapter are based on a nationally recognized model codes and Standards published by the International Code Council, Inc., The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), American Society for Testing and Materials (ASTM) and is made part of the MUBEC through incorporation by reference.

1. SECTION 1. PURPOSE AND SCOPE

   All building construction within the State of Maine shall be governed by the MUBEC. The MUBEC is adopted by the Technical Building Codes and Standards Board pursuant to Title 10 M.R.S. Chapter 1103. The primary objective of the Board is to establish a uniform building code throughout the State of Maine.

   This chapter sets forth the standards for the construction, alteration, movement, enlargement, replacement, repair, equipment, use and occupancy, location, maintenance, removal and demolition of every building or structure or any appurtenances connected or attached to such building or structure, with the exception of detached one and two-family dwellings and townhouses.

   EFFECTIVE DATE: The effective date of this Chapter is 90 days after approval by the Commissioner of the Department of Public Safety.

   1. SECTION 2. AUTHORITY

   The authority for this Chapter is Title 10 M.R.S. §9722, which provides that the Maine Technical Building Codes and Standards Board shall promulgate rules which adopt, amend, and maintain the Maine Uniform Building and Energy Code. Where conflicts occur between provisions of the MUBEC and those adopted by boards or programs within the Department of Professional & Financial Regulation, the codes, standards or rules adopted by such Boards or programs shall apply. This shall include, but not be limited to, the Maine Fuel Board Rules, Maine State Plumbing Code, Maine State Manufactured Housing Board Rules.

   1. SECTION 3. DEFINITIONS
   2. 1. ASHRAE. “ASHRAE” means The American Society of Heating, Refrigerating and Air-Conditioning Engineers.
   3. 2. ASTM. “ASTM” means American Society for Testing and Materials.
   4. 3. IBC. “IBC” means the International Building Code, published by the International Code Council, Inc., 2021 edition adopted as part of the MUBEC.
   5. 4. IMC. “IMC” means the International Mechanical Code, published by the International Code Council, Inc., 2021 edition (adopted as part of the MUBEC).
   6. 5. MUBEC. “MUBEC” means the Maine Uniform Building and Energy Code adopted pursuant to Title 10 M.R.S. §9271 et seq..
   7. 6. NFPA. “NFPA” means The National Fire Protection Association.
   8. 7. PFR. “PFR” means the State of Maine Office of Professional and Financial Regulation.
   9. 8. Technical Building Codes and Standards Board. “Technical Building Codes and Standards Board” means the board established pursuant to Title 5 M.R.S. §12004-G, subsection 5-A and Title 10 M.R.S. §9722.

      SECTION 4. INCORPORATION BY REFERENCE

   10. 1. The following Chapters of the 2021 International Mechanical Code, published by the International Code Council, Inc. are hereby adopted and incorporated by reference:
       1. A. Chapters 1 – 6
       2. B. Chapters 8 - 9

          C Chapters 11-12

       3. D. Chapters 14 -15
   11. 2. The following Chapters, and all appendices, of the IMC are specifically excluded from adoption:
       1. A. Chapters 7, 10, & 13
       2. B. Appendix A - C
2. 3. The following ASHRAE 62.1- 2019 edition are hereby incorporated by reference

4. The following ASHRAE 62.2- 2019 edition are hereby incorporated by reference

5. The following ASHRAE 90.1- 2019 edition are hereby incorporated by reference

6. The following ASTM E 1465-08 are hereby incorporated by reference

1. SECTION 5. REVISIONS TO THE IMC

   The following additions, insertions, deletions, and other changes are hereby made to the 2021 International Mechanical Code:

1. Generally in all Sections

1. Delete “International Fuel Gas Code.”
   1. Insert “NFPA 54 National Fuel Gas Code; Fire codes and standards adopted pursuant to Title 25 M.R.S §§ 2452 and 2465; and the Maine Fuel Board Rules and codes and standards adopted pursuant to Title 32 Chapter 139” in its place.

2. Generally in all Sections

1. Delete “International Plumbing Code”; and
   1. Insert “Maine State Plumbing Code, adopted pursuant to Title 32, M.R.S §3404-B” in its place.

3. Generally in all sections

Delete “International Fire Code” ; and

1. Insert “NFPA 1; Fire codes and standards adopted pursuant to Title 25 M.R.S. §§ 2452 and 2465” in its place.
2. 4. Section 101.1
   1. Delete [NAME OF JURISDICTION]; and

      Insert “State of Maine” in its place.

5. Section 102.7

Insert (after “new installations”) “see Maine Trade Board’s rules for compliance.”

6. Section 102.8.1

1. Insert (at the end of the section) “See Section 2 Authority of the MUBEC Chapter 7.”

7. Section 102.8.2

1. Insert (at the end of the section) “See Section 2 Authority of the MUBEC Chapter 7.”

8. Section 103

Delete Section 103 in its entirety.

9. Section 104.2

Insert (at the beginning of the text) “Where applicable,”

10. Section 104.3

Insert (at the beginning of the text) “Where applicable,”

11. Section 106.1.1

Delete Section 106.1.1 in its entirety.

12. Section 106.1.2

Delete Section 106.1.2 in its entirety.

13. Section 108.2

Delete all language after “Required inspections and testing.”; and

Insert “See Section 2 Authority of the MUBEC Chapter 7.” in its place.

14. Section 108.3

Delete all language after “Testing.”; and

Insert “See Section 2 Authority of the MUBEC Chapter 7.” in its place.

15. Section 109

Delete Section 109 in its entirety.

16. Section 114

Delete Section 114 in its entirety; and

Insert “See Section 2 Authority of the MUBEC Chapter 7.” in its place.

17. Section 115

Delete Section 115 in its entirety; and

Insert “See Section 2 Authority of the MUBEC Chapter 7.” in its place.

18. Section 202

Delete definition for “APPLIANCE VENTED”; and

1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

Delete definition for “APPLIANCE TYPE. High-heat appliance”; and

1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.
   1. Delete definition for “APPLIANCE TYPE. Low-heat appliance (residential appliance)”; and

      Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “APPLIANCE TYPE. Medium-heat appliance”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “AUTOMATIC BOILER”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “BOILER”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “CHIMNEY”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “CHIMNEY. Factory-built chimney”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “CHIMNEY. Masonry chimney”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “CHIMNEY. Metal chimney”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “CHIMNEY CONNECTOR”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

      Delete definition for “CLOSED COMBUSTION SOLID-FUEL-BURNING APPLIANCE”; and

      Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “COMBUSTIBLE MATERIAL”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “CONVERSION BURNER”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “[FG] DIRECT-VENT APPLIANCES”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “DRAFT”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “DRAFT. Induced draft”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “DRAFT. Natural draft”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “DUCT FURNACE”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “[FG] FLOOR FURNACE”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “[FG] FLUE GASES”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “[FG] FUEL GAS”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “FUEL OIL”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “FUEL-OIL PIPING SYSTEM”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “FURNACE”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “FURNACE ROOM”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

      Delete all references to gas appliances from “HEAVY-DUTY COOKING APPLICANCE” definition; and

      Insert (at the end of the definition) “For gas appliances, see codes and standards adopted by PFR Board.”

      Delete all references to gas appliances from “LIGHT-DUTY COOKING APPLIANCE” definition; and

      Insert (at the end of the definition) “For gas appliances, see codes and standards adopted by PFR Board.”

   Delete definition for “[F] LOWER FLAMMABLE LIMIT (LFL)”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “LOW-PRESSURE HOT-WATER-HEATING BOILER”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “LOW-PRESSURE STEAM-HEATING BOILER”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

      Delete all references to gas appliances from “MEDIUM-DUTY COOKING APPLIANCE” definition; and

      Insert (at the end of the definition) “For gas appliances, see codes and standards adopted by PFR Board.”

   Delete definition for “MODULAR BOILER”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “NONCOMBUSTIBLE MATERIALS”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “PRESSURE VESSELS”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “PRESSURE VESSELS- REFRIGERANT”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete (from definition of “[FG] ROOM HEATER, VENTED”) “or liquid fuel”; and

   1. Insert (at the end of the definition)“For liquid fuel, see codes and standards adopted by PFR Board.”

   Delete definition for “STEAM-HEATING BOILER”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “TOILET ROOM”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “TOILET ROOM. Type L vent”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “VENT CONNECTOR”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

   Delete definition for “WATER HEATER”; and

   1. Insert “See definition in codes and standards adopted by PFR Board.” in its place.

19. Section 301.4

Insert (at the end of the sentence) “and as applicable under Maine State Plumbing Code.”

20. Section 301.7

1. Insert (after “Section 105” text) “and applicable codes and standards adopted by PFR boards.”

21. Section 301.8

Delete all language after “Labeling.”; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

22. Section 301.9

Delete all language after “Labeling Information.”; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

23. Section 301.12

1. Insert (at the end of the last sentence) “to be in accordance with codes and standards adopted by PFR boards.”

24. Section 303.3

Delete all language after “Prohibited Locations.”; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

25. Section 303.4

Delete all language after “Protection from damage.”; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

26. Section 303.5

Delete all language after “Indoor locations.”; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

27. Section 303.8

Delete all language after “Elevator shafts.”; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

28. Section 304.2

Delete “this code”; and

Insert “applicable codes and standards adopted by PFR boards” in its place.

29. Section 304.3 and 304.3.1

Delete all language after “Elevation of ignition source.”; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

30. Section 304.4

Delete all language after “Prohibited equipment and appliance location”; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

31. Section 305.4

Delete all language, including the table, after “Interval of support.”; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

32. Section 306

Delete Section 306.1 through 306.5 in their entirety.; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

33. Section 307

Delete Section 307.1 through 307.3 in their entirety; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

34. Section 308

Delete Section 308.1 through 308.4 in their entirety; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

35. Section 309.1

Delete Section 309.1 in its entirety; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

36. Section 312.1

1. Insert (at the end of the paragraph) “Refer to applicable codes and standards adopted by PFR boards.”

37. Section 502.9.10

Delete Section 502.9.10 in its entirety; and

Insert “See applicable codes and standards adopted by PFR boards.” in its place.

38. Section 502.16

1. Insert (after the heading) “Section 502.16 and its subsections in the International Mechanical Code shall not apply to Compressed Natural Gas or Liquified Natural Gas, but only to Hydrogen and other lighter-than air motor fuels. For Compressed and Liquified Natural Gas requirements, refer to the Maine Fuel Board Rules.”

39. Section 504

1. Insert (to create numbered exceptions, before the written exception) “1.”
   1. Insert (as a second exception)“2. Section 504 does not apply to class I and class II gas dryers. For class I and class II gas dryers, see applicable codes and standards adopted by PFR boards.”

40. Section 512

Delete Section 512 in its entirety; and

Insert ASTM E 1465-08 in its place.

41. Chapter 7

1. Delete IMC Chapter 7 language in its entirety; and
   1. Insert “Fire codes and standards adopted pursuant to Title 25 M.R.S §§ 2452 and 2465 and the Maine Fuel Board Rules and codes and standards adopted pursuant to Title 32 Chapter 139” in its place.

42. Chapter 8 – All Sections

1. Delete IMC Chapter 8, language in its entirety; and
   1. Insert “Refer to NFPA 211; Fire codes and standards adopted pursuant to Title 25 M.R.S §§ 2452 and 2465” in its place.

43. Chapter 9 – Various Sections

1. Delete IMC Chapter 9 Sections 902, 903, 905, 906, 907, 909, 910, 911, 916, 917, 918, 919, 920, 921, and 922 in their entirety; and

Insert ”See applicable codes and standards adopted by PFR boards.” in its place.

44. Chapter 10 – All Sections

1. Delete IMC Chapter 10, all sections, language in their entirety; and
   1. Insert “Fire codes and standards adopted pursuant to Title 25 M.R.S §§ 2452 and 2465 and the Maine Fuel Board Rules; and codes and standards adopted pursuant to Title 32 Chapter 139” in its place.

45. Chapter 13 – All Sections

1. Delete IMC Chapter 13, all sections, language in their entirety; and
   1. Insert “Fire codes and standards adopted pursuant to Title 25 M.R.S §§ 2452 and 2465 and the Maine Fuel Board Rules; and codes and standards adopted pursuant to Title 32 Chapter 139” in its place.

46. Section 1401.1

1. Insert (after “process heating”) “and NFPA 1; Fire codes and standards adopted pursuant to Title 25 M.R.S §§ 2452 and 2465; and the Maine Fuel Board Rules and codes and standards adopted pursuant to Title 32 Chapter 139” in its place.

47. Chapter 15

Delete (“ASHRAE 15” edition year reference) “2019”; and

Insert “2022” as the edition year, in its place.

STATUTORY AUTHORITY:

Title 10 M.R.S. §9722

EFFECTIVE DATE:

September 20, 2021 – filing 2021-181

March 4, 2025 – filing 2025-048

APAO ACCESSIBILITY CHECK: July 31, 2025

TRANSFER OF AUTHORITY TO ADMINISTER AND ENFORCE RULE: The authority to administer and enforce this rule (formerly 16-642 C.M.R. Ch. 7) was transferred to the Maine Office of Community Affairs on September 24, 2025 pursuant to PL 2025, c. 388.