Title 24 · California Energy Code

Which mechanical systems require acceptance testing and Certificates of Acceptance before occupancy?

Before a building can be occupied in California, many mechanical systems (listed in §120.5 for nonresidential and §160.3(d) for multifamily) must be acceptance‑tested to the NA7 procedures and a signed Certificate of Acceptance submitted to the local enforcement agency. Tests include outdoor‑air ventilation, economizers, duct leakage (often the **6%** threshold), DCV, supply‑fan controls, hydronic controls, FDD/AFDD, and more; certified technicians and required signatures are specified in the Code and Mechanical Appendix E.

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Last reviewed: July 6, 2026

What the code requires — plain English

Before a final occupancy permit is issued, the California Energy Code requires that certain mechanical systems be acceptance-tested and a signed Certificate of Acceptance submitted to the enforcement agency. The list of required systems for nonresidential buildings is in § 120.5 and the list for multifamily common areas and dwelling units is in § 160.3(d); each required test is performed to the procedures in the Reference Nonresidential Appendix NA7 (e.g., NA7.5.1, NA7.5.3, etc.) .

The single most important rule: any mechanical system named in § 120.5 (nonresidential) or § 160.3(d) (multifamily) must be acceptance-tested to the referenced NA7 procedure and a Certificate of Acceptance provided to the Authority Having Jurisdiction before occupancy is granted.

Requirements in detail

Summary table — which systems, which NA7 test, and where the requirement appears in the Energy Code:

System / control NA7 test reference (decision‑relevant) Code Reference
Outdoor air ventilation systems NA7.5.1 § 120.5(a)1; § 160.3(d)3.A
Constant‑volume single‑zone AC & heat pump unit controls NA7.5.2 § 120.5(a)2; § 160.3(d)3.B
Duct leakage / duct systems (when subject to testing criteria) NA7.5.3 (duct leakage test) § 120.5(a)3; duct sealing criteria in § 120.4(g) and § 160.3(c)/160.3(d)
Air economizers, DOAS, HRV, ERV NA7.5.4 § 120.5(a)4; § 160.3(d)3.D (exception for factory‑certified units)
Demand control ventilation (DCV) NA7.5.5 § 120.5(a)5; § 160.3(d)3.E
Supply fan variable flow controls NA7.5.6 § 120.5(a)6; § 160.3(d)3.F
Hydronic variable flow controls / valve leakage NA7.5.7 / NA7.5.9 § 120.5(a)7; § 160.3(d)3.G
Supply water temperature reset / reset controls NA7.5.8 / NA7.5.15 § 120.5(a)9 / 15; § 160.3(d)3.I / O
Automatic demand shed controls NA7.5.10 § 120.5(a)10; § 160.3(d)3.J
FDD (DX units) / AFDD (AHUs, terminals) NA7.5.11 / NA7.5.12 § 120.5(a)11-12; § 160.3(d)3.K-L
Distributed energy storage DX AC, TES, chillers with reset NA7.5.13 / NA7.5.14 / NA7.5.16 § 120.5(a)13-16; § 160.3(d)3.M-N, P
Occupant sensing zone controls, cooling tower controls NA7.5.17 / NA7.5.18 § 120.5(a)17-19; § 160.3(d)3.R
Multifamily central ventilation ducts & ERV/HRV (dwelling units) NA7.18.3 / NA7.18.4 § 160.3(d)2.A‑B (multifamily dwelling units)

Key decision dimensions and numeric thresholds (excerpted and summarized from the Code and NA7 cross‑references):

Threshold / defined term Value / rule Code reference
Duct leakage maximum (for specified new duct systems) 6% of nominal air handler airflow (confirmed via NA7.5.3) § 120.4(g)1.i / NA7.5.3
Space‑conditioning system size to qualify for 6% rule < 5,000 ft² conditioned floor area § 120.4(g)1.c
Duct area in unconditioned/outdoor spaces threshold > 25% of total duct surface area § 120.4(g)1.c
Return duct length / bends (residential sizing note) ≤ 30 ft and ≤ 180° total bends (Table 160.3‑A) § 160.3(g) (Table 160.3‑A)
Certified test technician (CMATT) required When Title 24, Part 1 §10‑103.2 requires certification § 160.3(b) — CMATT ID disclosed on Certificate of Acceptance

Notes on the table: each NA7.x test contains the step‑by‑step functional test procedure and the Certificate of Acceptance form reference (see NA7 and Appendix E/Forms). The Energy Code text lists the systems and points to NA7 tests; Appendix E of the Mechanical Code describes the certificate forms and signatures required. See the code excerpts cited above for the full test mapping and form names.

Exceptions & special cases

  • Systems serving healthcare facilities are generally excepted from § 120.5 acceptance requirements (Exception to § 120.5) — check the healthcare exception text in § 120.5 for details.
  • Factory‑installed, Commissioned Economizers: If an air economizer is installed by the HVAC manufacturer and the manufacturer has certified factory calibration and testing to the Commission, the economizer is not required to comply with the functional testing portion of NA7.5.4 (Exception to § 120.5(a)4 and § 160.3(d)3.D). Do not assume this exception applies unless the manufacturer certification is documented.
  • Duct testing alternative: Duct systems not meeting the new‑duct criteria in § 120.4(g)1 must still meet CMC Section 603.9.2 leakage testing instead of NA7.5.3. Verify which testing route applies before deciding the test procedure.
  • Multifamily dwelling units vs common areas: § 160.3(d) separates requirements for systems serving common areas (full NA7 list) and those serving dwelling units (a narrower set including certain central ventilation/ERV tests) — apply the correct subsection to each system.
  • When Title 24 Part 1 requires a certified technician (CMATT), the CMATT’s certification ID must be shown on the Certificate of Acceptance and the test must be performed by a CMATT or employer meeting the Part 1 requirements § 160.3(b).

Certificate of Acceptance: who signs and what is required

  • The Certificate must be completed and submitted to the enforcement agency prior to final occupancy. Appendix E (Mechanical Code) and the Energy Code require the field technician who performed the tests to sign, and a Responsible Person (contractor or RDP of record) to review and sign (field tech and responsible person signatures). The AHJ will not release final occupancy until required Certificates of Acceptance are submitted. Forms are located in Appendix E (E.806.0 / MECH‑ forms).
  • When certification is required by Part 1 §10‑103.2, the technician must be a CMATT and must disclose the CMATT ID on the Certificate of Acceptance § 160.3(b).
  • The Certificate documents the NA7 test used, measurements taken, pass/fail, corrective actions, and final signature blocks for the field technician and responsible person (see Mechanical Appendix E test form list).

Common mistakes

  • Assuming a system is exempt because it is “small” without checking the Code thresholds (e.g., duct leakage criteria tied to < 5,000 ft² and > 25% duct area in unconditioned spaces). Always confirm the sectional thresholds before skipping a NA7 test. § 120.4(g)1 / § 120.5.
  • Forgetting to submit the Certificate of Acceptance (or submitting it unsigned or without the CMATT ID when required). The AHJ can withhold final occupancy until correct certificates are received (Appendix E).
  • Using the wrong test standard: some duct systems must follow CMC §603.9.2 instead of NA7.5.3 — check whether the duct meets the NA7 applicability criteria first.
  • Misreading the economizer exception: a manufacturer‑certified economizer can be exempt from the functional testing portion only if factory testing/certification to the Commission is documented — don’t assume factory‑installed means exempt. § 120.5(a)4 / § 160.3(d)3.D.
  • Not using a CMATT when Part 1 requires certification — the CMATT ID is a mandatory field on the Certificate of Acceptance § 160.3(b).

Worked example — concrete scenario with numbers

Scenario: You install a new constant‑volume single‑zone packaged air conditioner serving a 3,000 ft² retail space. Ductwork runs through the plenum and 40% of the duct surface is in an unconditioned attic. The unit has an air economizer (field‑installed), and nominal air handler flow is 2,000 cfm.

Which acceptance tests and certificates are required before occupancy?

  • Duct leakage: the system meets the new‑duct criteria (constant volume single zone, serves < 5,000 ft², and > 25% of ducts in unconditioned space) so the ducts must be sealed to ≤ 6% leakage of nominal air handler flow and tested per NA7.5.3. For this unit 6% of 2,000 cfm = 120 cfm allowable leakage at the test condition; the NA7.5.3 procedure and Certificate MECH‑4A (or NA7 form) must be completed. § 120.4(g)1 / § 120.5(a)3.
  • Unit controls: the constant‑volume single‑zone unitary controls must be functionally tested per NA7.5.2 and reported on the appropriate certificate form § 120.5(a)2.
  • Outdoor air/economizer: because the economizer is field‑installed (not factory‑certified), perform the air economizer functional test per NA7.5.4 and document via the Certificate (MECH‑5A / NA7 form) § 120.5(a)4. If it had been factory‑certified and Commission‑approved, the economizer functional test could be exempted — but only with documentation.
  • Who signs: the field technician performing the NA7 tests signs the Certificate of Acceptance; if Part 1 requires a CMATT, the CMATT ID must be shown on the certificate. The responsible person (contractor or RDP) reviews and signs the certificate before submittal to the AHJ. Appendix E describes the form(s) and signature requirements — the AHJ will not issue final occupancy without these certificates.

Related provisions (quick list)

  • § 120.5 — Required nonresidential mechanical system acceptance (list and NA7 mapping).
  • § 120.4(g) — Duct sealing applicability and the 6% leakage threshold reference to NA7.5.3.
  • § 160.3(d) — Multifamily common area and dwelling unit acceptance testing and required Certificates of Acceptance.
  • § 160.3(b) — When CMATT certification is required and CMATT disclosure on the Certificate of Acceptance.
  • Mechanical Code Appendix E (E.803–E.806) — Certificate of Acceptance forms, roles (field technician/Responsible Person) and submission rules (AHJ will not release final occupancy without certificates).
  • CMC § 603.9.2 — Alternative duct leakage testing requirements where NA7.5.3 does not apply (see § 120.4(g)2).

Code references

Grounded in the retrieved California Energy Code — click a citation to read the verbatim passage:

  • § 180.2 High relevance — show source text

    G. Insulation shall be protected from damage, including that due to sunlight, moisture, equipment maintenance and wind but not limited to the following: Insulation exposed to weather shall be suitable for outdoor service; e.g., protected by aluminum, sheet metal, painted canvas or plastic cover. Cellular foam insulation shall be protected as above or painted with a coating that is water retardant and provides shielding from solar radiation that can cause degradation of the material. H. Duct systems shall be tested in accordance with i or ii below: i. New duct systems that meet the criteria in Subsections a, b and c below or ductwork that is part of a system that meets the criteria of Section 180.2(b)2B shall be sealed to a leakage rate not to exceed 6 percent of the nominal air handler airflow rate as confirmed through acceptance testing, in accordance with Reference Nonresidential Appendix NA7.5.3. a. The duct system provides conditioned air to an occupiable space for a constant volume, single zone, space-conditioning system; and b. The space-conditioning system serves less than 5,000 square feet of conditioned floor area; and c. The combined surface area of the ducts located in the following spaces is more than 25 percent of the total surface area of the entire duct system:

    I. Outdoors; or

    II. In a space directly under a roof that has a U- factor greater than the U- factor of the ceiling, or if the roof does not meet the requirements of Section 170.2(a)1; or III. In a space directly under a roof that has fixed vents or openings to the outside or unconditioned

    spaces; or IV. In an unconditioned crawl space; or V. In other unconditioned spaces. ii. All duct systems that do not meet the criteria in Section 160.3(c)2H shall meet the duct leakage testing requirements of CMC Section 603.9.2.

    (d) Mechanical acceptance testing.

    1. Common areas. Before an occupancy permit is granted, the following systems and equipment serving multifamily common areas shall be certified as meeting the Acceptance Requirements for Code Compliance, as specified by Reference Nonresidential Appendix NA7. These systems and equipment shall also comply with the applicable requirements of Section

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    160.3(d)3. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements: A. Outdoor air ventilation systems shall be tested in accordance with NA7.5.1. B. Constant volume, single zone air conditioning and heat pump unit controls shall be tested in accordance with NA7.5.2. C. Duct systems shall be tested in accordance with NA7.5.3 where either: a. They are new duct systems; or b. They are part of an altered system. D. Air economizers, DOAS, HRV or ERV systems shall be tested in accordance with NA7.5.4. Exception to Section 160.3(d)1D: Air economizers installed by the HVAC system manufacturer and certified to the Commission as being factory calibrated and tested are not required to comply with the Functional Testing section of the Air Economizer Controls acceptance test as described in NA7.5.4.2. E. Demand control ventilation systems required by Section 160.2(c)3 shall be tested in accordance with NA7.5.5.

  • § 160.3 High relevance — show source text

    (d) Mechanical acceptance testing.

    1. Common areas. Before an occupancy permit is granted, the following systems and equipment serving multifamily common areas shall be certified as meeting the Acceptance Requirements for Code Compliance, as specified by Reference Nonresidential Appendix NA7. These systems and equipment shall also comply with the applicable requirements of Section

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    160.3(d)3. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements: A. Outdoor air ventilation systems shall be tested in accordance with NA7.5.1. B. Constant volume, single zone air conditioning and heat pump unit controls shall be tested in accordance with NA7.5.2. C. Duct systems shall be tested in accordance with NA7.5.3 where either: a. They are new duct systems; or b. They are part of an altered system. D. Air economizers, DOAS, HRV or ERV systems shall be tested in accordance with NA7.5.4. Exception to Section 160.3(d)1D: Air economizers installed by the HVAC system manufacturer and certified to the Commission as being factory calibrated and tested are not required to comply with the Functional Testing section of the Air Economizer Controls acceptance test as described in NA7.5.4.2. E. Demand control ventilation systems required by Section 160.2(c)3 shall be tested in accordance with NA7.5.5. F. Supply fan variable flow controls shall be tested in accordance with NA7.5.6. G. Hydronic system variable flow controls shall be tested in accordance with NA7.5.7 and NA7.5.9. H. Boilers or chillers that require isolation controls as specified by Section 170.2(c)4Iii or 170.2(c)4Iiii shall be tested in accordance with NA7.5.7.

    I. Hydronic systems with supply water temperature reset controls shall be tested in accordance with NA7.5.8.

    J. Automatic demand shed controls shall be tested in accordance with NA7.5.10.

    K. Fault detection and diagnostics (FDD) for packaged direct expansion units shall be tested in accordance with NA7.5.11. L. Automatic fault detection and diagnostics (FDD) for air handling units and zone terminal units shall be tested in accordance with NA7.5.12.

    M. Distributed energy storage DX AC systems shall be tested in accordance with NA7.5.13. N. Thermal energy storage (TES) systems shall be tested in accordance with NA7.5.14. O. Supply air temperature reset controls shall be tested in accordance with NA7.5.15. P. Water-cooled chillers served by cooling towers with condenser water reset controls shall be tested in accordance with NA7.5.16.

    Q. When an energy management control system is installed, it shall functionally meet all of the applicable requirements of Part 6.

  • § 5.6. High relevance — show source text

    1. Supply fan variable flow controls shall be tested in accordance with NA7.5.6.

    2. Hydronic system variable flow controls shall be tested in accordance with NA7.5.7 and NA7.5.9.

    3. Boiler or chillers that require isolation controls as specified by Section 140.4(k)2 or 140.4(k)3 shall be tested in accordance with NA7.5.7.

    4. Hydronic systems with supply water temperature reset controls shall be tested in accordance with NA7.5.8.

    5. Automatic demand shed controls shall be tested in accordance with NA7.5.10.

    6. Fault Detection and Diagnostics (FDD) for Packaged Direct-Expansion Units shall be tested in accordance with NA7.5.11.

    7. Automatic fault detection and diagnostics (FDD) for air handling units and zone terminal units shall be tested in accordance with NA7.5.12.

    8. Distributed Energy Storage DX AC Systems shall be tested in accordance with NA7.5.13.

    9. Thermal Energy Storage (TES) Systems shall be tested in accordance with NA7.5.14.

    10. Supply air temperature reset controls shall be tested in accordance with NA7.5.15.

    11. Water-cooled chillers served by cooling towers with condenser water reset controls shall be tested in accordance with NA7.5.16.

    12. When an energy management control system is installed, it shall functionally meet all of the applicable requirements of Part 6.

    13. Occupant sensing zone controls shall be tested in accordance with NA7.5.17.

    14. Conductivity controls and overflow alarms for open and closed-circuit cooling towers shall be tested according to NA7.5.18.

    (b) When certification is required by Title 24, Part 1, Section 10-103.2, the acceptance testing specified by Section 120.5(a) shall be performed by a certified mechanical acceptance test technician (CMATT). If the CMATT is operating as an employee, the CMATT shall

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    NONRESIDENTIAL, HOTEL/MOTEL OCCUPANCIES, AND COVERED PROCESSES—MANDATORY REQUIREMENTS

    be employed by a certified mechanical acceptance test employer. The CMATT shall disclose on the certificate of acceptance a valid CMATT certification identification number issued by an approved acceptance test technician certification provider. The CMATT shall complete all certificate of acceptance documentation in accordance with the applicable requirements in Section 10-103(a)4.

    Note: Authority cited: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402(a)-(b), 25402.1, 25402.4, 25402.5, 25402.8 and 25943, Public Resources Code .

    SECTION 120.6—MANDATORY REQUIREMENTS FOR COVERED PROCESSES

    Nonresidential and hotel/motel buildings shall comply with the applicable requirements of Sections 120.6(a) through 120.6(k), and the applicable requirements of Sections 110.2(a) and 120.3.

    (a) Mandatory requirements for refrigerated warehouses.

  • § 160.2 High relevance — show source text

    E. Demand control ventilation systems required by Section 160.2(c)3 shall be tested in accordance with NA7.5.5. F. Supply fan variable flow controls shall be tested in accordance with NA7.5.6. G. Hydronic system variable flow controls shall be tested in accordance with NA7.5.7 and NA7.5.9. H. Boilers or chillers that require isolation controls as specified by Section 170.2(c)4Iii or 170.2(c)4Iiii shall be tested in accordance with NA7.5.7.

    I. Hydronic systems with supply water temperature reset controls shall be tested in accordance with NA7.5.8.

    J. Automatic demand shed controls shall be tested in accordance with NA7.5.10.

    K. Fault detection and diagnostics (FDD) for packaged direct expansion units shall be tested in accordance with NA7.5.11. L. Automatic fault detection and diagnostics (FDD) for air handling units and zone terminal units shall be tested in accordance with NA7.5.12.

    M. Distributed energy storage DX AC systems shall be tested in accordance with NA7.5.13. N. Thermal energy storage (TES) systems shall be tested in accordance with NA7.5.14. O. Supply air temperature reset controls shall be tested in accordance with NA7.5.15. P. Water-cooled chillers served by cooling towers with condenser water reset controls shall be tested in accordance with NA7.5.16.

    Q. When an energy management control system is installed, it shall functionally meet all of the applicable requirements of Part 6.

    R. Occupant sensing zone controls shall be tested in accordance with NA7.5.17. 2. Multifamily dwelling units. Before an occupancy permit is granted, the following systems and equipment serving multifamily dwelling units shall be certified as meeting the acceptance requirements for code compliance, as specified by the Reference Nonresidential Appendix NA7. These systems and equipment shall also comply with the applicable requirements of Section 160.3(d)3. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements: A. Multifamily building central ventilation ducts subject to Section 160.2(b)2C shall be leak tested in accordance with NA7.18.3.

    B. Multifamily building central ventilation system heat recovery or energy recovery systems in multifamily buildings with four or more habitable stories shall be tested in accordance with NA7.18.4.

    1. When certification is required by Title 24, Part 1, Section 10-103.2, the acceptance testing specified by Section 160.3(d)1 and 2 shall be performed by a Certified Mechanical Acceptance Test Technician (CMATT). If the CMATT is operating as an employee, the CMATT shall be employed by a Certified Mechanical Acceptance Test Employer. The CMATT shall disclose on the Certificate of Acceptance a valid CMATT certification identification number issued by an approved Acceptance Test Technician Certification Provider. The CMATT shall complete all Certificate of Acceptance documentation in accordance with the applicable requirements in Section 10-103(a)4.
    TABLE 160.3-A—RETURN DUCT SIZING FOR SINGLE RETURN DUCT SYSTEMS Col2 Col3
    Return duct length shall not exceed 30 feet and shall contain no more than 180 degrees of bend.
  • § 5.3 High relevance — show source text

    (g) Duct sealing. Duct systems shall comply with Subsection 1 or 2 below:

    1. New duct systems that meet the criteria in Subsections A, B, C and D below shall be sealed to a leakage rate not to exceed 6 percent of the nominal air handler airflow rate as confirmed through acceptance testing, in accordance with Reference Nonresidential Appendix NA7.5.3; A. The duct system does not serve a healthcare facility; and B. The duct system provides conditioned air to an occupiable space for a constant volume, single zone, space-conditioning system; and C. The space-conditioning system serves less than 5,000 square feet of conditioned floor area; and D. The combined surface area of the ducts located outdoors or in unconditioned space is more than 25 percent of the total surface area of the entire duct system.
    2. New duct systems that are not subject to testing under Section 120.4(g)1 shall instead meet the duct leakage testing requirements of CMC Section 603.9.2.

    Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, and 25943, Public Resources Code.

    SECTION 120.5—REQUIRED NONRESIDENTIAL MECHANICAL SYSTEM ACCEPTANCE

    Nonresidential and hotel/motel buildings shall comply with the applicable requirements of Sections 120.5(a) through 120.5(b).

    Exception to Section 120.5: Systems serving healthcare facilities.

    (a) Before an occupancy permit is granted, the following equipment and systems shall be certified as meeting the Acceptance Requirements for Code Compliance, as specified by the Reference Nonresidential Appendix NA7. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements:

    1. Outdoor air ventilation systems shall be tested in accordance with NA7.5.1.

    2. Constant volume, single zone unitary air conditioning and heat pump unit controls shall be tested in accordance with NA7.5.2.

    3. Duct systems that are subject to testing under Section 120.4(g)1, Section 141.0(b)2Di or Section 141.0(b)2Dii shall be tested in accordance with NA7.5.3.

    4. Air economizers, DOAS, HRV or ERV systems shall be tested in accordance with NA7.5.4. Exception 1 to Section 120.5(a)4: Air economizers installed by the HVAC system manufacturer and certified to the Commission as being factory calibrated and tested are not required to comply with the Functional Testing section of the air economizer controls acceptance test as described in NA7.5.4.2. Exception 2 to Section 120.5(a)4: The DOAS, HRV, or ERV unit that does not meet the exhaust air heat recovery ratio as specified in Section 140.4(q)1 or does not include bypass or control to disable energy recovery as specified in Section 140.4(q)2.

    5. Demand control ventilation systems required by Section 120.1(c)3 shall be tested in accordance with NA7.5.5.

    6. Supply fan variable flow controls shall be tested in accordance with NA7.5.6.

  • § 5.1. High relevance — show source text

    (a) Before an occupancy permit is granted, the following equipment and systems shall be certified as meeting the Acceptance Requirements for Code Compliance, as specified by the Reference Nonresidential Appendix NA7. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements:

    1. Outdoor air ventilation systems shall be tested in accordance with NA7.5.1.

    2. Constant volume, single zone unitary air conditioning and heat pump unit controls shall be tested in accordance with NA7.5.2.

    3. Duct systems that are subject to testing under Section 120.4(g)1, Section 141.0(b)2Di or Section 141.0(b)2Dii shall be tested in accordance with NA7.5.3.

    4. Air economizers, DOAS, HRV or ERV systems shall be tested in accordance with NA7.5.4. Exception 1 to Section 120.5(a)4: Air economizers installed by the HVAC system manufacturer and certified to the Commission as being factory calibrated and tested are not required to comply with the Functional Testing section of the air economizer controls acceptance test as described in NA7.5.4.2. Exception 2 to Section 120.5(a)4: The DOAS, HRV, or ERV unit that does not meet the exhaust air heat recovery ratio as specified in Section 140.4(q)1 or does not include bypass or control to disable energy recovery as specified in Section 140.4(q)2.

    5. Demand control ventilation systems required by Section 120.1(c)3 shall be tested in accordance with NA7.5.5.

    6. Supply fan variable flow controls shall be tested in accordance with NA7.5.6.

    7. Hydronic system variable flow controls shall be tested in accordance with NA7.5.7 and NA7.5.9.

    8. Boiler or chillers that require isolation controls as specified by Section 140.4(k)2 or 140.4(k)3 shall be tested in accordance with NA7.5.7.

    9. Hydronic systems with supply water temperature reset controls shall be tested in accordance with NA7.5.8.

    10. Automatic demand shed controls shall be tested in accordance with NA7.5.10.

    11. Fault Detection and Diagnostics (FDD) for Packaged Direct-Expansion Units shall be tested in accordance with NA7.5.11.

    12. Automatic fault detection and diagnostics (FDD) for air handling units and zone terminal units shall be tested in accordance with NA7.5.12.

    13. Distributed Energy Storage DX AC Systems shall be tested in accordance with NA7.5.13.

    14. Thermal Energy Storage (TES) Systems shall be tested in accordance with NA7.5.14.

    15. Supply air temperature reset controls shall be tested in accordance with NA7.5.15.

    16. Water-cooled chillers served by cooling towers with condenser water reset controls shall be tested in accordance with NA7.5.16.

    17. When an energy management control system is installed, it shall functionally meet all of the applicable requirements of Part 6.

    18. Occupant sensing zone controls shall be tested in accordance with NA7.5.17.

    19. Conductivity controls and overflow alarms for open and closed-circuit cooling towers shall be tested according to NA7.5.18.

  • § 803.2 High relevance — show source text

    (1) Visual inspection of the equipment and installation.

    (2) Review of the certification requirements.

    (3) Functional tests of the systems and controls.

    E 803.2 Construction Documents. Details of commissioning acceptance requirements shall be incorporated into the construction documents, including information that describes the details of the functional tests to be performed. This information shall be permitted to be integrated into the specifications for testing and air balancing, energy management and control system, equipment startup procedures or commissioning. It is possible that the work will be performed by a combination of the test and balance (TAB) contractor,

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    ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

    APPENDIX E

    mechanical/electrical contractor, and the energy management control system (EMCS) contractor, so applicable roles and responsibilities shall be clearly called out.

    E 803.2.1 Roles and Responsibilities. The roles and responsibilities of the persons involved in commissioning acceptance are included in Section E 803.2.1.1 through Section E 803.2.1.3.

    E 803.2.1.1 Field Technician. The field technician shall be responsible for performing and documenting the results of the acceptance procedures on the certificate of acceptance forms. The field technician shall sign the certificate of acceptance to certify that the information he provides on the certificate of acceptance is true and correct.

    E 803.2.1.2 Responsible Person. The responsible person shall be the contractor or registered design professional of record. A certificate of acceptance shall be signed by a responsible person to take responsibility for the scope of work specified by the certificate of acceptance document. The responsible person shall perform the field testing and verification work, and where this is the case, the responsible person shall complete and sign both the field technician’s signature block and the responsible person’s signature block on the certificate of acceptance form. The responsible person assumes responsibility for the acceptance testing work performed by the field technician agent or employee. E 803.2.1.3 Certificate of Acceptance. The certificate of acceptance shall be submitted to the Authority Having Jurisdiction in order to receive the final certificate of occupancy. The Authority Having Jurisdiction shall not release a final certificate of occupancy unless the submitted certificate of acceptance demonstrates that the specified systems and equipment have been shown to be performing in accordance with the applicable acceptance requirements. The Authority Having Jurisdiction has the authority to require the field technician and responsible person to demonstrate competence, to its satisfaction. Certificate of acceptance forms are located in Section E 806.0.

    E 804.0 Commissioning Tests. E 804.1 General. Functional tests shall be performed on new equipment and systems installed in either new construction or retrofit applications in accordance with this section. The appropriate certificate of acceptance form along with each specific test shall be completed and submitted to the Authority Having Jurisdiction before a final occupancy permit can be granted.

    E 804.2 Tests. Functional testing shall be performed on the devices and systems listed in this section. The functional test results are documented using the applicable certificate of acceptance forms shown in parenthesis and located in Section E 806.0. The functional tests shall be performed in accordance with Section E 805.0 using the following forms:

    (1) Minimum ventilation controls for constant and variable air volume systems (Form MECH-2A).

  • § 804.3.2 High relevance — show source text

    This is typically done prior to signing a certificate of compliance. E 804.3.2 Construction Inspection. The installing contractor, registered design professional of record, owner’s agent, or the person responsible for certification of the acceptance testing on the certificate of acceptance (responsible person) shall perform a construction inspection prior to testing to ensure that the equipment that is installed is capable of complying with the requirements of this appendix and is calibrated. The installation of associated systems and equipment necessary for proper system operation is required to be completed prior to the testing.

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    ), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

    APPENDIX E

    E 804.3.3 Acceptance Testing. One or more field technicians shall perform the acceptance testing; identify performance deficiencies; ensure that they are corrected; and where necessary, repeat the acceptance procedures until the specified systems and equipment are performing in accordance with the acceptance requirements. The field technician who performs the testing shall sign the certificate of acceptance to certify the information has been provided to document the results of the acceptance procedures is true and correct.

    The responsible person shall review the test results from the acceptance requirement procedures provided by the field technician and sign the certificate of acceptance to certify compliance with the acceptance requirements. The responsible person shall be permitted to perform the field technician’s responsibilities, and shall then sign the field technician declaration on the certificate of acceptance to certify that the information on the form is true and correct.

    E 804.3.4 Certificate of Occupancy. The Authority Having Jurisdiction shall not issue the final certificate of occupancy until required certificates of acceptance are submitted. Copies of completed, signed certificates of acceptance are required to be posted, or made available with the permit(s), and shall be made available to the Authority Having Jurisdiction.

    E 805.0 HVAC System Tests.

    E 805.1 Variable Air Volume Systems (Form MECH- 2A). This test ensures that adequate outdoor air ventilation is provided through the variable air volume air handling unit at two representative operating conditions. The test consists of measuring outdoor air values at maximum flow and at or near minimum flow. The test verifies that the minimum volume of outdoor air is introduced to the air handling unit where the system is in occupied mode at these two conditions of supply airflow. This test shall be performed in conjunction with supply fan variable flow controls test procedures to reduce the overall system testing time as both tests use the same two conditions of airflow for their measurements.

    E 805.1.1 Test Procedure. The procedure for performing a functional test for variable air volume systems shall be in accordance with Section E 805.1.1.1 and Sec tion E 805.1.1.2.

    E 805.1.1.1 Construction Inspection. Prior to functional testing, verify and document that the system controlling outside airflow is calibrated either in the field or factory.

    E 805.1.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

    Step 1: Where the system has an outdoor air economizer, force the economizer high limit to disable economizer control (e.g., for a fixed dry-bulb high limit, lower the setpoint below the current outdoor air temperature).

    Step 2: Adjust supply airflow to either the sum of the minimum zone airflows or 30 percent of the total design airflow. Verify and document the following:

  • § 7.13. High relevance — show source text

    A certificate of acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements specified in NA 7.13.

    (f) Mandatory requirements for elevators. Elevators shall meet the following requirements:

    1. The light power density for the luminaires inside the elevator cab shall be no greater than 0.6 watts per square foot. Exception to Section 120.6(f)1: Interior signal lighting and interior display lighting are not included in the calculation of lighting power density.

    2. Elevator cab ventilation fans for cabs without space conditioning shall not exceed 0.33 watts per cfm as measured at maximum speed.

    3. When the elevator cab is stopped and unoccupied with doors closed for over 15 minutes, the cab interior lighting and ventilation fans shall be switched off until elevator cab operation resumes.

    4. Lighting and ventilation shall remain operational in the event that the elevator cabin gets stuck when passengers are in the cabin.

    5. Elevator Lighting and Ventilation Control Acceptance. Before an occupancy permit is granted for elevators subject to 120.6(f), the following equipment and systems shall be certified as meeting the Acceptance Requirement for Code Compli

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    ance, as specified by the Reference Nonresidential Appendix NA7. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements specified in NA7.14.

    Exception to Section 120.6(f): Elevators located in healthcare facilities.

    (g) Mandatory requirements for escalators and moving walkways .

    1. Escalators and moving walkways located in airports, hotels, and transportation function areas shall automatically slow to the minimum permitted speed in accordance with ASME A17.1/CSA B44 when not conveying passengers.
    2. Escalators and Moving Walkways Acceptance. Before an occupancy permit is granted for escalators and moving walkways subject to 120.6(g), the following equipment and systems shall be certified as meeting the Acceptance Requirement for Code Compliance, as specified by the Reference Nonresidential Appendix NA7. A Certificate of Acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements specified in NA7.15.

    (h) Mandatory requirements for controlled environment horticulture (CEH) spaces.

    1. Indoor growing, dehumidification. Dehumidification equipment shall be one of the following: A. Dehumidifiers subject to regulation under federal appliance standards tested in accordance with 10 CFR 430.23(z) and Appendix X or X1 to Subpart B of 10 CFR Part 430 as applicable, and complying with 10 CFR 430.32(v)2; B. Integrated HVAC system with on-site heat recovery designed to fulfill at least 75 percent of the annual energy for dehumidification reheat;

    C. Chilled water system with on-site heat recovery designed to fulfill at least 75 percent of the annual energy for dehumidification reheat; or

    D. Solid or liquid desiccant dehumidification system for system designs that require dew point of 50°F or less. 2. Indoor growing, electrical power distribution systems. Electrical power distribution systems serving CEH spaces shall be designed so that a measurement device is capable of monitoring the electrical energy usage of aggregate horticultural lighting load. 3.

  • § 140.9 High relevance — show source text

    Listed energy recovery devices with a sensible heat recovery effectiveness of not less than 40 percent on at least 50 percent of the total exhaust airflow; or iv. A minimum of 75 percent of makeup air volume that is:

    a. Unheated or heated to no more than 60°F; and

    b. Uncooled or cooled without the use of mechanical cooling.

    Exception to Section 140.9(b)2B: Existing hoods not being replaced as part of an addition or alteration. 3. Kitchen exhaust system acceptance. Before an occupancy permit is granted for a commercial kitchen subject to Section 140.9(b), the following equipment and systems shall be certified as meeting the acceptance requirements for code compliance, as specified by the Reference Nonresidential Appendix NA7. A certificate of acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements specified in NA7.11.

    Exception to Section 140.9(b): Healthcare facilities.

    (c) Prescriptive requirements for laboratory and factory exhaust systems.

    1. Airflow reduction requirements. Building laboratory exhaust systems shall be able to reduce zone exhaust and makeup airflow rates to the occupied and unoccupied minimum exhaust airflow rates based on demand and sensed occupancy as follows:

    A. Occupied minimum exhaust airflow. When occupant sensing controls sense occupants in the space, the minimum exhaust and makeup airflow rates shall be the greater of: i. User-defined airflow not to exceed 1.0 cfm/ft [2] (equivalent to 6 air changes per hour for a 10-foot high ceiling); or ii. The regulated minimum occupied circulation rate documented to comply with code, accreditation, or facility environmental health and safety department requirements; or iii. The minimum needed to maintain occupied pressurization. B. Unoccupied minimum exhaust airflow. Within 20 minutes of no occupancy being detected by any occupant sensors covering the space, the minimum exhaust and makeup airflow rates shall be the greater of: i. User-defined airflow not to exceed 0.67 cfm/ft [2] (equivalent to 4 air changes per hours for a 10-foot high ceiling);

    or

    ii. The regulated minimum unoccupied circulation rate documented to comply with code, accreditation, or facility environmental health and safety department requirements; or iii. The minimum needed to maintain unoccupied pressurization. C. Applicable equipment and systems shall be certified as meeting the acceptance requirements for code compliance, as specified by the reference Nonresidential Appendix NA7.16. A certificate of acceptance shall be submitted to the enforcement agency that certifies that the equipment and systems meet the acceptance requirements specified in Nonresidential Appendix NA7.16.

    Exception to Section 140.9(c)1: New zones on an existing constant volume exhaust system. 2. Exhaust System Transfer Air. Conditioned supply air delivered to any space with mechanical exhaust shall comply with the requirements of Section 140.4(o). 3. Fan System Power Consumption. All newly installed fan exhaust systems serving a laboratory or factory with a design exhaust fan system airflow rate greater than 10,000 cfm shall meet Subsection A and either B, C, or D. Exhaust air in laboratories or factories includes all indoor air and gases removed by the exhaust system, including exhaust air from fume hoods, hazardous exhaust flows, or other manifolded exhaust streams. Exhaust fan system airflow rate is the total of the airflow rates entering the exhaust fans, which includes exhaust air and bypass air but does not include entrained or induced airflow downstream of the exhaust fans.

  • § 803.2.1.3 High relevance — show source text

    The responsible person shall perform the field testing and verification work, and where this is the case, the responsible person shall complete and sign both the field technician’s signature block and the responsible person’s signature block on the certificate of acceptance form. The responsible person assumes responsibility for the acceptance testing work performed by the field technician agent or employee. E 803.2.1.3 Certificate of Acceptance. The certificate of acceptance shall be submitted to the Authority Having Jurisdiction in order to receive the final certificate of occupancy. The Authority Having Jurisdiction shall not release a final certificate of occupancy unless the submitted certificate of acceptance demonstrates that the specified systems and equipment have been shown to be performing in accordance with the applicable acceptance requirements. The Authority Having Jurisdiction has the authority to require the field technician and responsible person to demonstrate competence, to its satisfaction. Certificate of acceptance forms are located in Section E 806.0.

    E 804.0 Commissioning Tests. E 804.1 General. Functional tests shall be performed on new equipment and systems installed in either new construction or retrofit applications in accordance with this section. The appropriate certificate of acceptance form along with each specific test shall be completed and submitted to the Authority Having Jurisdiction before a final occupancy permit can be granted.

    E 804.2 Tests. Functional testing shall be performed on the devices and systems listed in this section. The functional test results are documented using the applicable certificate of acceptance forms shown in parenthesis and located in Section E 806.0. The functional tests shall be performed in accordance with Section E 805.0 using the following forms:

    (1) Minimum ventilation controls for constant and variable air volume systems (Form MECH-2A).

    (2) Zone temperature and scheduling controls for constant volume, single-zone, unitary air conditioner and heat pump systems (Form MECH-3A).

    (3) Duct leakage on a subset of small single-zone systems depending on the ductwork location (Form MECH-4A).

    (4) Air economizer controls for economizers that are not factory installed and tested (Form MECH-5A).

    (5) Demand-controlled ventilation control systems (Form MECH-6A).

    (6) Supply fan variable flow controls (Form MECH-7A).

    (7) Valve leakage for hydronic variable flow systems and isolation valves on chillers and boilers in plants with more than one chiller or boiler being served by the same primary pumps through a common header (Form MECH8A).

    (8) Supply water temperature reset control strategies programmed into the building automation system for water systems (e.g., chilled, hot, or condenser water) (Form MECH-9A).

    (9) Hydronic variable flow controls on a water system where the pumps are controlled by variable frequency drives (e.g., chilled and hot water systems; water-loop heat pump systems) (Form MECH-10A).

    (10)Automatic demand shed control (Form MECH-11A).

    (11)Fault detection and diagnostic for DX units (Form MECH-12A).

    (12)Automatic fault detection and diagnostic systems (AFDD) (Form MECH-13A).

    (13)Distributed energy storage DEC/DX AC systems (Form MECH-14A).

    (14)Thermal energy storage (TES) systems (Form MECH15A). E 804.3 Acceptance Process. The functional testing process shall comply with Section E 804.3.1 through Section E 804.3.4.

  • § 6.4. High relevance — show source text
    1. Outdoor lighting controls shall be tested in accordance with Reference Nonresidential Appendix NA7.8; and
    2. Lighting systems receiving the Institutional Tuning Power Adjustment Factor shall be tested in accordance with Reference Nonresidential Appendix NA7.6.4.
    3. Demand responsive controls required to control controlled receptacles shall be tested in accordance with Reference Nonresidential Appendix NA7.6.5.

    (b) Lighting control installation certificate requirements. To be recognized for compliance with Part 6 an installation certificate shall be submitted in accordance with Section 10-103(a) for any lighting control system, energy management control system, interlocked lighting system, lighting power adjustment factor, or additional wattage available for a videoconference studio, in accordance with the following requirements, as applicable:

    1. Certification that when a lighting control system is installed to comply with lighting control requirements in Part 6 it complies with the applicable requirements of Section 110.9; and complies with Reference Nonresidential Appendix NA7.7.1.

    2. Certification that when an energy management control system is installed to function as a lighting control required by Part 6 it functionally meets all applicable requirements for each application for which it is installed, in accordance with Sections 110.9, 130.0 through 130.5, 140.6 through 150.0, and 150.2; and complies with Reference Nonresidential Appendix NA7.7.2.

    3. Reserved.

    4. Reserved.

    5. Certification that interlocked lighting systems used to serve an approved area comply with Section 140.6(a)1; and comply with Reference Nonresidential Appendix NA7.7.4.

    6. Certification that lighting controls installed to earn a lighting power adjustment factor (PAF) comply with Section 140.6(a)2; and comply with Reference Nonresidential Appendix NA7.7.5.

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    1. Certification that additional lighting wattage installed for a videoconference studio complies with Section 140.6(c)2Gvii; and complies with Reference Nonresidential Appendix NA7.7.6.

    (c) When certification is required by Title 24, Part 1, Section 10-103.1, the acceptance testing specified by Section 130.4 shall be performed by a certified lighting controls acceptance test technician (CLCATT). If the CLCATT is operating as an employee, the CLCATT shall be employed by a certified lighting controls acceptance test employer. The CLCATT shall disclose on the Certificate of Acceptance a valid CLCATT certification identification number issued by an approved acceptance test technician certification provider. The CLCATT shall complete all certificate of acceptance documentation in accordance with the applicable requirements in Section 10-103(a)4.

    Note: Authority cited: Sections 25402, 25402.1 and 25213, Public Resources Code . Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.5, 25402.8, and 25943, Public Resources Code .

    SECTION 130.5—ELECTRICAL POWER DISTRIBUTION SYSTEMS

Frequently asked questions

Who must sign the Certificate of Acceptance?

The field technician who performed the tests must sign; a Responsible Person (contractor or registered design professional of record) must also review and sign. When Part 1 requires a CMATT, the CMATT must provide their certification ID on the form.

If an economizer was factory‑installed, do I still have to test it?

If the economizer is factory‑installed and the manufacturer has certified it to the Commission as factory calibrated and tested, the functional testing portion of NA7.5.4 is not required — but only with documented manufacturer/Commission certification. § 120.5(a)4 / § 160.3(d)3.D.

What happens if I don’t submit the Certificates before occupancy?

The Authority Having Jurisdiction may withhold the final Certificate of Occupancy until the required Certificates of Acceptance are submitted and show compliance with the NA7 acceptance requirements. Appendix E makes this explicit.

Which duct systems use the 6% leakage rule?

New duct systems that meet all criteria in § 120.4(g)1 (constant volume single zone; serves < 5,000 ft²; > 25% duct surface area in outdoor/unconditioned spaces) must be sealed to ≤ 6% leakage and tested per NA7.5.3. Otherwise CMC §603.9.2 applies.

Do multifamily dwelling units have the same acceptance tests as common areas?

No — multifamily common areas are subject to the broader NA7 list in § 160.3(d)1, while dwelling units have a narrower set of required tests (e.g., central ventilation ducts and ERV/HRV tests NA7.18.x) under § 160.3(d)2. Apply the correct subsection based on where the equipment serves.

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