CMC · California Mechanical Code

What are the rules for automatic control devices and building automation systems?

The California Mechanical Code requires heating appliances to have listed automatic shutoffs for pilot/ignition failure and limits on outlet air temperature (e.g., furnaces ≤250°F; electric duct heaters ≤200°F auto reset) and requires building automation systems to provide—and document—a local control capability that works if the BAS network fails (see **§ 306.1** and **§ 306.2**).

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Last reviewed: July 6, 2026

What the code requires — 2–4 sentences

Heating appliances must use listed devices that shut off the fuel supply if the pilot or ignition fails, with limited exceptions; furnaces and electric duct heaters must have air‑outlet temperature limit controls set at prescribed maxima and located or protected as required — see § 306.1 . A building automation system (BAS) must be designed to provide localized control when the BAS network fails, and that localized capability must be documented in the construction documents — see § 306.2 .

The single most important rule: heating equipment must fail safe — pilots/igniters must not allow uncontrolled fuel flow, and automation systems must not leave equipment unusable when the network goes down (see § 306.1 and § 306.2).

Requirements in detail

Automatic control devices — § 306.1

  • Required function: heating appliances shall be equipped with a listed device that will shut off the fuel supply to the main burner(s) in the event of pilot or ignition failure. Liquefied petroleum gas (LP‑gas) appliances must have a listed automatic device that will shut off gas flow to the pilot if ignition fails. § 306.1 .
  • Exceptions: the listed shutoff devices are not required for ranges or cooking tops, log lighters, lights, or other open‑burner manually operated appliances, or listed appliances that do not require such devices, and certain specific industrial appliances approved by the AHJ. § 306.1 .
  • Remote controls: heating appliances whose manual fuel controls are not readily accessible from the main portion of the building shall be provided with remote controls. § 306.1 .
  • Temperature limit controls (forced‑air / gravity furnaces): forced‑air and gravity‑type warm air furnaces must have a listed air outlet temperature limit control that cannot be set above 250°F (121°C) and that is located in the bonnet or plenum within 2 feet (610 mm) of the discharge (or located in accordance with the appliance listing). § 306.1 .
  • Electric duct heaters: must have an approved automatic reset air outlet temperature limit control that limits outlet air to not exceed 200°F (93°C). The electric elements also must be protected by fusible links or a manual reset temperature limit control that prevents outlet air temperatures in excess of 250°F (121°C). § 306.1 .

Decision‑relevant dimensions and values

Decision dimension Required value / condition (bolded thresholds) Applies to Code Reference
Fuel shutoff on pilot/ignition failure Listed device to shut off fuel to main burner(s) All heating appliances (gas, oil, etc.) § 306.1
LP‑gas pilot protection Listed device to shut off gas to the pilot on ignition failure LP‑gas air‑burning heating appliances § 306.1
Exceptions No shutoff required for ranges, cooking tops, log lighters, lights, open‑burner manually operated appliances, etc. Appliances specifically listed in exception § 306.1
Furnace outlet temp limit ≤ 250°F (121°C); control located within 2 ft (610 mm) of discharge or per listing Forced‑air and gravity warm air furnaces § 306.1
Electric duct heater outlet control Automatic reset limit ≤ 200°F (93°C) Electric duct heaters § 306.1
Electric element protection Fusible links or manual reset to prevent > 250°F (121°C) outlet Electric heating elements in duct heaters § 306.1
Remote control requirement Provide remote controls when manual fuel controls are not readily accessible Any heating appliance with inaccessible controls § 306.1

Building automation systems (BAS) — § 306.2

  • Core requirement (brief): a BAS shall provide for localized control in the event of network failure, and that capability shall be specified in the construction documentation. § 306.2 .
  • What the code says (and what it does not): the code requires the existence of a localized‑control capability and documentation of it, but it does not prescribe the exact technical method (e.g., whether local operator panels, hardwired overrides, or local automatic controllers are used). Because the text is concise, the exact implementation details are left to the designer and the Authority Having Jurisdiction (AHJ). § 306.2 .

Exceptions & special cases

  • The explicit exceptions in § 306.1 mean that many cooking appliances and manually operated open burners may be exempt from listed automatic shutoff devices; do not assume every gas appliance needs the same safety shutoff — check the appliance listing and the exception language in § 306.1 .
  • The furnace outlet limit control location can be per the appliance listing; if the appliance listing provides different allowable locations, follow the listing or the AHJ's direction (see § 306.1). § 306.1 .
  • § 306.2 contains an OSHPD notation ([OSHPD 1]) in the code text snippet; projects under OSHPD jurisdiction should note that OSHPD may apply additional requirements or interpretations. § 306.2 .

If you need a prescriptive list of acceptable localized control implementations (e.g., required minimum functions of a local panel), the code text retrieved here does not specify those details — that level of prescription must come from project documents, manufacturer listings, or guidance from the AHJ. § 306.2 .

Common mistakes

  • Assuming networked BAS control alone meets code: the BAS must include localized control when the network fails and this must be documented (failure to specify this in construction documents is a common omission). § 306.2 .
  • Setting furnace outlet limit above 250°F (121°C) or locating the limit control farther than 2 ft (610 mm) from the discharge (unless listed otherwise). § 306.1 .
  • Forgetting the automatic reset requirement or the 200°F (93°C) limit for electric duct‑heater automatic reset outlet controls. § 306.1 .
  • Omitting documentation: the localized‑control capability for BAS must be specified in the construction documents; leaving it implicit is a frequent rejection item. § 306.2 .
  • Misreading the exceptions: some appliances are exempt from listed shutoffs — confirm whether the appliance is one of the listed exceptions before omitting safety devices. § 306.1 .

Worked example

Scenario: A medium office building has a BAS that controls two rooftop forced‑air furnaces and electric duct heaters in a mechanical room. The design team must show compliance with § 306.1 and § 306.2.

Steps to apply the code requirements:

  1. Furnaces: install a listed air outlet temperature limit control that cannot be set above 250°F (121°C) and locate it within 2 ft (610 mm) of the furnace discharge (or provide documentation that the appliance listing allows a different location). Cite: § 306.1 .
    • Example numeric check: the installed limit control has a maximum setpoint of 230°F — compliant because it is ≤ 250°F and is mounted 1.5 ft from the discharge (≤ 2 ft). § 306.1 .
  2. Electric duct heaters: equip with an approved automatic reset outlet temperature limit that limits outlet air to ≤ 200°F (93°C). Also provide fusible links or a manual reset temperature limit device on the heater elements to prevent outlet temperatures above 250°F (121°C). Confirm the automatic reset control is listed/approved. § 306.1 .
    • Example numeric check: automatic reset trips at 195°F — compliant for the automatic reset requirement (≤ 200°F); fusible link rated to open before outlet would exceed 250°F. § 306.1 .
  3. BAS network failure plan: the BAS design documents must specify the localized control capability (for example: local mechanical room operator panel, manual start/stop and setpoint controls at the appliance, or local automatic controllers) so that when the network is down the furnaces and duct heaters remain operable and controllable. The code requires the capability and documentation but does not mandate one specific method — the design narrative and drawings must state the chosen approach. Cite: § 306.2 .

Related provisions

  • § 305.6 — Outdoor locations (appliance requirements for outdoors) .
  • § 307.0 — Labeling requirements for appliances (general labeling) .
  • § 307.1 — Fuel‑burning appliances: nameplate and information requirements .
  • § 304.1 — Accessibility for service (accessibility to appliances and service panels) .
  • Appendix E (Commissioning / acceptance testing) — Functional tests and certificates of acceptance for controls and BAS‑related items (see the MECH forms and acceptance process) .

Code references

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

  • CMC § 209.1.4 High relevance — show source text

    ** Automatic time switch control devices or system shall:

    1. Be capable of programming different schedules for weekdays and weekends; and

    2. Have program backup capabilities that prevent the loss of the device’s schedules for at least 7 days and the device’s time and date setting for at least 72 hours if power is interrupted. A6.209.1.4 Occupant sensors, motion sensors and vacancy sensors. Occupant sensors, motion sensors and vacancy sensors shall be capable of automatically turning off all the lights in an area no more than 30 minutes after the area has been vacated and shall have a visible status signal that indicates that the device is operating properly or that it has failed or malfunctioned. The visible status signal may have an override switch that turns the signal off. In addition, ultrasonic and microwave devices shall have a built-in mechanism that allows calibration of the sensitivity of the device to room movement in order to reduce the false sensing of occupants and shall comply with either Subsection A6.209.1.4.1 or A6.209.1.4.2 below, as applicable: A6.209.1.4.1 If the device emits ultrasonic radiation as a signal for sensing occupants within an area, the device shall:

    3. Have had a Radiation Safety Abbreviated Report submitted to the Center for Devices and Radiological Health, Federal Food and Drug Administration, under 21 Code of Federal Regulations, Section 1002.12 (1996) and a copy of the report shall have been submitted to the California Energy Commission; and

    4. Emit no audible sound; and

    5. Not emit ultrasound in excess of the decibel (dB) values shown in Table A6.209.1-A, measured no more than 5 feet from the source, on axis.

    A6.209.1.4.2 If the device emits microwave radiation as a signal for sensing occupants within the area, the device shall:

    1. Comply with all applicable provisions in 47 Code of Federal Regulations, Parts 2 and 15 (1996) and have an approved Federal Communications Commission Identifier that appears on all units of the device and that has been submitted to the California Energy Commission; and

    2. Not emit radiation in excess of 1 milliwatt per square centimeter measured at no more than 5 centimeters from the emission surface of the device; and

    3. Have permanently affixed to it installation instructions recommending that it be installed at least 12 inches from any area normally used by room occupants. A6.209.1.5 Multilevel occupant sensor. Multilevel occupant sensors shall have an automatic OFF function that turns off all the lights and either an automatic or a manually controlled ON function capable of meeting all the multilevel and uniformity requirements of Section A6.209.2.2 for the controlled lighting. The first stage shall be capable of activating between 30–70 percent of the lighting power in a room either through an automatic or manual action and may be a switching or dimming system. After that event occurs the device shall be capable of all of the following actions when manually called to do so by the occupant:

    4. Activating the alternate set of lights.

    5. Activating 100 percent of the lighting power.

    6. Deactivating all lights. A6.209.1.6 Automatic daylighting control devices. Automatic daylighting control devices used to control lights in daylit zones shall:

    7. Be capable of reducing the power consumption of the general lighting in the controlled area by at least two thirds in response to the availability of daylight; and

  • CMC § 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.

  • CMC § 207.1.1 High relevance — show source text

    **
    A6.207.1.1 Efficiency.
    A6.207.1.2 Controls for heat pumps with supplementary electric resistance heaters.
    A6.207.1.3 Thermostats.
    A6.207.1.4 Gas-and oil-fired furnace standby loss controls.||



    |



    || |A6.207.2 Space conditioning systems.
    A6.207.2.1 Supply air temperature reset controls.
    A6.207.2.2 Electric resistance heating.
    A6.207.2.3 Heat rejection systems.
    A6.207.2.4 Hydronic system measures.
    A6.207.2.5 Air distribution system duct leakage sealing.
    A6.207.2.6 Variable air volume control for single zone systems.||





    |





    || |A6.207.3 Service water-heating systems and equipment.
    A6.207.3.1 Certification by manufacturers.
    A6.207.3.2 Efficiency.
    A6.207.3.3 Installation.||


    |


    || |A6.207.4 Natural gas central furnaces, cooking equipment and pool and spa heaters.
    Pilot lights prohibited.||||| |A6.207.5 Controls for space-conditioning systems.
    A6.207.5.1 Thermostatic controls for each zone.
    A6.207.5.2 Criteria for zonal thermostatic controls.
    A6.207.5.3 Heat pump controls.
    A6.207.5.4 Dampers for air supply and exhaust equipment.
    A6.207.5.5 Automatic demand shed controls.||




    |




    || |A6.207.6 Pipe insulation.||||| |SECTION A6.209 Lighting||||| |A6.209.1 Lighting control devices, ballasts and luminaires.
    A6.209.1.1 All devices: Instructions and calibration.
    A6.209.1.2 Indicator lights.
    **A6.209.1.3 Automatic time switch control devices.

  • CMC § 909.12.4 High relevance — show source text

    [F] 909.12.4 Automatic control. Where completely automatic control is required or used, the automatic-control sequences shall be initiated from an appropriately zoned automatic sprinkler system complying with Section 903.3.1.1, manual controls provided with ready access for the fire department and any smoke detectors required by engineering analysis.

    [F] 909.13 Control air tubing. Control air tubing shall be of sufficient size to meet the required response times. Tubing shall be flushed clean and dry prior to final connections and shall be adequately supported and protected from damage. Tubing passing through concrete or masonry shall be sleeved and protected from abrasion and electrolytic action.

    [F] 909.13.1 Materials. Control-air tubing shall be hard-drawn copper, Type L, ACR in accordance with ASTM B42, ASTM B43, ASTM B68/B68M, ASTM B88, ASTM B251 and ASTM B280. Fittings shall be wrought copper or brass, solder type in accordance with ASME B16.18 or ASME B16.22. Changes in direction shall be made with appropriate tool bends. Brass compression-type fittings shall be used at final connection to devices; other joints shall be brazed using a BCuP-5 brazing alloy with solidus above 1,100°F (593°C) and liquids below 1,500°F (816°C). Brazing flux shall be used on copper-to-brass joints only.

    Exception: Nonmetallic tubing used within control panels and at the final connection to devices provided that all of the following conditions are met:

    1. Tubing shall comply with the requirements of Chapter 6 of the California Mechanical Code .
    2. Tubing and connected devices shall be completely enclosed within a galvanized or paint-grade steel enclosure having a minimum thickness of 0.0296 inch (0.7534 mm) (No. 22 gage). Entry to the enclosure shall be by copper tubing with a protective grommet of neoprene or Teflon or by suitable brass compression to male barbed adapter.
    3. Tubing shall be identified by appropriately documented coding.
    4. Tubing shall be neatly tied and supported within the enclosure. Tubing bridging cabinets and doors or moveable devices shall be of sufficient length to avoid tension and excessive stress. Tubing shall be protected against abrasion. Tubing connected to devices on doors shall be fastened along hinges.

    [F] 909.13.2 Isolation from other functions. Control tubing serving other than smoke control functions shall be isolated by automatic isolation valves or shall be an independent system.

    [F] 909.13.3 Testing. Control air tubing shall be tested at three times the operating pressure for not less than 30 minutes without any noticeable loss in gauge pressure prior to final connection to devices.

    [F] 909.14 Marking and identification. The detection and control systems shall be clearly marked at all junctions, accesses and terminations.

    [F] 909.15 Control diagrams. Identical control diagrams showing all devices in the system and identifying their location and function shall be maintained current and kept on file with the fire code official, the fire department and in the fire command center in a format and manner approved by the fire code official.

  • CMC § 306.2 High relevance — show source text

    Forced-air and gravity-type warm air furnaces shall be equipped with a listed air outlet temperature limit control that cannot be set for temperatures exceeding 250°F (121°C). Such controls shall be located in the bonnet or plenum, within 2 feet (610 mm) of the discharge side of the heating element of gravity furnaces or in accordance with the conditions of listing.

    Electric duct heaters shall be equipped with an approved automatic reset air outlet temperature limit control that will limit the outlet air temperature to not exceed 200°F (93°C). The electric elements of the heater shall be equipped with fusible links or a manual reset temperature limit control that will prevent outlet air temperature in excess of 250°F (121°C).

    306.2 Building Automation Systems. [OSHPD 1] Building automation systems shall provide for localized con- trol in the event of network failure. This capability shall be specified in the construction documentation.

    307.0 Labeling.

    307.1 Fuel-Burning Appliances. Fuel-burning heating appliances shall bear a permanent and legible factory-applied nameplate on which shall appear:

    (1) The name or trademark of the manufacturer.

    (2) The approved fuel input rating of the appliance, expressed in Btu/h (kW).

    (3) The model number or equivalent.

    (4) The serial number.

    (5) Instructions for the lighting, operation, and shutdown of the appliance.

    (6) The type of fuel approved for use with the appliance.

    (7) The symbol of an approved agency certifying compliance of the equipment with recognized standards.

    (8) Required clearances from combustible surfaces on which or adjacent to which it is permitted to be mounted.

    307.2 Electric Heating Appliances. Electric heating appliances shall bear a permanent and legible factory-applied nameplate on which shall appear:

    (1) The name or trademark of the manufacturer.

    (2) The model number or equivalent.

    (3) The serial number.

    (4) The electrical rating in volts, amperes (or watts), and, for other than single phase, the number of phases.

    (5) The output rating in Btu/h (kW).

    (6) The electrical rating in volts, amperes, or watts of each field-replaceable electrical component.

    (7) The symbol of an approved agency certifying compliance of equipment with recognized standards.

    (8) Required clearances from combustible surfaces on which or adjacent to which it is permitted to be mounted.

    An appliance shall be accompanied by clear and complete installation instructions, including required clearances from combustibles other than mounting or adjacent surfaces, and temperature rating of field-installed wiring connections exceeding 140°F (60°C). 307.3 Heat Pump and Electric Cooling Appliances. Heat pumps and electric cooling appliances shall bear a permanent and legible factory-applied nameplate on which shall

    appear:

    (1) The name or trademark of the manufacturer.

    (2) The model number or equivalent.

    (3) The serial number.

    (4) The amount of refrigerant.

    (5) The refrigerant designation.

    (6) The factory test pressures or pressures applied.

    (7) The electrical rating in volts, amperes, and, for other than single phase, the number of phases.

    (8) The output rating in Btu/h (kW).

    (9) The electrical rating in volts, amperes, or watts of each field replaceable electrical component.

    (10)The symbol of an approved agency certifying compliance of the equipment with recognized standards.

  • CMC § 305.6 High relevance — show source text

    (3) Where a drainage pan pipe is installed, the material of the piping shall be rated for the temperature rating of the water heater and shall be approved for use with the liquid being discharged.

    (4) Discharge from a relief valve into a drainage pan shall be prohibited. 305.6 Outdoor Locations. Appliances installed in outdoor locations shall be in accordance with the following:

    (1) Listed for outdoor installation.

    (2) Provided with approved protection from the outdoor elements that can affect the operation, durability, or safety of such appliances and in accordance with the manufacturer’s installation instructions.

    (3) Outdoor cooking appliances shall comply with Section 922.0.

    306.0 Automatic Control Devices.

    306.1 General. Heating appliances shall be equipped with a listed device or devices that will shut off the fuel supply to the main burner or burners in the event of pilot or ignition failure. Liquefied petroleum gas-air-burning heating appli

    2025 CALIFORNIA MECHANICAL CODE 55

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

    GENERAL REGULATIONS

    ances shall be equipped with a listed automatic device or devices that will shut off the flow of gas to the pilot in the event of ignition failure.

    Exception: The listed shutoff devices shall not be required on range or cooking tops, log lighters, lights, or other openburner manually operated appliances, or listed appliances not requiring such devices and specific industrial appliances as approved by the Authority Having Jurisdiction.

    Heating appliances whose manual fuel controls are not readily accessible from the main portion of the building being heated shall be equipped with remote controls.

    Forced-air and gravity-type warm air furnaces shall be equipped with a listed air outlet temperature limit control that cannot be set for temperatures exceeding 250°F (121°C). Such controls shall be located in the bonnet or plenum, within 2 feet (610 mm) of the discharge side of the heating element of gravity furnaces or in accordance with the conditions of listing.

    Electric duct heaters shall be equipped with an approved automatic reset air outlet temperature limit control that will limit the outlet air temperature to not exceed 200°F (93°C). The electric elements of the heater shall be equipped with fusible links or a manual reset temperature limit control that will prevent outlet air temperature in excess of 250°F (121°C).

    306.2 Building Automation Systems. [OSHPD 1] Building automation systems shall provide for localized con- trol in the event of network failure. This capability shall be specified in the construction documentation.

    307.0 Labeling.

    307.1 Fuel-Burning Appliances. Fuel-burning heating appliances shall bear a permanent and legible factory-applied nameplate on which shall appear:

    (1) The name or trademark of the manufacturer.

    (2) The approved fuel input rating of the appliance, expressed in Btu/h (kW).

    (3) The model number or equivalent.

    (4) The serial number.

    (5) Instructions for the lighting, operation, and shutdown of the appliance.

    (6) The type of fuel approved for use with the appliance.

    (7) The symbol of an approved agency certifying compliance of the equipment with recognized standards.

    (8) Required clearances from combustible surfaces on which or adjacent to which it is permitted to be mounted.

  • CMC § 804.3 Medium relevance — show source text

    (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.

    E 804.3.1 Plan Review. 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 review the plans and specifications to ensure that they are in accordance with the acceptance requirements. 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.

    2025 CALIFORNIA MECHANICAL CODE 481

    ), 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.

  • CMC § 9-47 Medium relevance — show source text

    This includes stairway pressurization fans; smoke exhaust fans; supply, return and exhaust fans; elevator shaft fans and other operating equipment used or intended for smoke control purposes. 2. OPEN-AUTO-CLOSE control over individual dampers relating to smoke control and that are controlled from other sources within the building. 3. ON-OFF or OPEN-CLOSE control over smoke control and other critical equipment associated with a fire or smoke emergency and that can only be controlled from the firefighter’s control panel.

    Exceptions:

    1. Complex systems, where approved, where the controls and indicators are combined to control and indicate all elements of a single smoke zone as a unit.

    2025 CALIFORNIA BUILDING CODE 9-47

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    FIRE PROTECTION AND LIFE SAFETY SYSTEMS

    1. Complex systems, where approved, where the control is accomplished by computer interface using approved, plain English commands.

    [F] 909.16.3 Control action and priorities. The firefighter’s control panel actions shall be as follows:

    1. ON-OFF and OPEN-CLOSE control actions shall have the highest priority of any control point within the building. Once issued from the firefighter’s control panel, automatic or manual control from any other control point within the building shall not contradict the control action. Where automatic means are provided to interrupt normal, nonemergency equipment operation or produce a specific result to safeguard the building or equipment including, but not limited to, duct freezestats, duct smoke detectors, high-temperature cutouts, temperature-actuated linkage and similar devices, such means shall be capable of being overridden by the firefighter’s control panel. The last control action as indicated by each firefighter’s control panel switch position shall prevail. Control actions shall not require the smoke control system to assume more than one configuration at any one time.

    Exception: Power disconnects required by the California Electrical Code. 2. Only the AUTO position of each three-position firefighter’s control panel switch shall allow automatic or manual control action from other control points within the building. The AUTO position shall be the NORMAL, nonemergency, building control position. Where a firefighter’s control panel is in the AUTO position, the actual status of the device (on, off, open, closed) shall continue to be indicated by the status indicator described in Section 909.16.1. Where directed by an automatic signal to assume an emergency condition, the NORMAL position shall become the emergency condition for that device or group of devices within the zone. Control actions shall not require the smoke control system to assume more than one configuration at any one time.

    [F] 909.17 System response time. Smoke-control system activation shall be initiated immediately after receipt of an appropriate automatic or manual activation command. Smoke control systems shall activate individual components (such as dampers and fans) in the sequence necessary to prevent physical damage to the fans, dampers, ducts and other equipment. For purposes of smoke control, the firefighter’s control panel response time shall be the same for automatic or manual smoke control action initiated from any other building control point. The total response time, including that necessary for detection, shutdown of operating equipment and smoke control system startup, shall allow for full operational mode to be achieved before the conditions in the space exceed the design smoke condition. Upon receipt of an alarm condition at the fire alarm control panel, fans, dampers and automatic doors shall have achieved their proper operating state and the final status shall be indicated at the smoke control panel within 90 seconds.

  • CMC § 305.6 Medium relevance — show source text

    305.6 Outdoor Locations . . . . . . . . . . . . . 55

    306.0 Automatic Control Devices . . . . . . . 55

    306.1 General. . . . . . . . . . . . . . . . . . . . . . 55

    306.2 Building Automation Systems . . . . 56

    2025 CALIFORNIA MECHANICAL CODE

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

    TABLE OF CONTENTS

    307.0 Labeling . . . . . . . . . . . . . . . . . . . . . 56

    307.1 Fuel-Burning Appliances . . . . . . . . 56

    307.2 Electric Heating Appliances . . . . . . 56

    307.3 Heat Pump and Electric Cooling Appliances . . . . . . . . . . . . . . . . . . . 56

    307.4 Absorption Units . . . . . . . . . . . . . . . 56

    308.0 Improper Location. . . . . . . . . . . . . . 57

    308.1 General. . . . . . . . . . . . . . . . . . . . . . 57

    309.0 Workmanship . . . . . . . . . . . . . . . . . 57

    309.1 Engineering Practices. . . . . . . . . . . 57

    309.2 Concealing Imperfections . . . . . . . . 57

    309.3 Installation Practices. . . . . . . . . . . . 57

    310.0 Condensate Wastes and Control . . 57

    310.1 Condensate Disposal . . . . . . . . . . . 57

    310.2 Condensate Control . . . . . . . . . . . . 57

    310.3 Condensate Waste Pipe Material and Sizing. . . . . . . . . . . . . . . . . . . . 57

    Table 310.3 Minimum Condensate Pipe Size. . . 57

    310.4 Appliance Condensate Drains . . . . 58

    310.5 Point of Discharge . . . . . . . . . . . . . 58

    310.6 Condensate Waste from

    Air-Conditioning Coils . . . . . . . . . . . 58

    310.7 Female Plastic Connections . . . . . . 58

    311.0 Heating or Cooling Air System . . . . 58

    311.1 Source . . . . . . . . . . . . . . . . . . . . . . 58

    311.2 Air Filters . . . . . . . . . . . . . . . . . . . . 58

    311.3 Prohibited Sources . . . . . . . . . . . . . 58

    311.4 Return-Air Limitations . . . . . . . . . . . 58

    311.5 California Energy Code Requirements for Residential

    Air Filtration . . . . . . . . . . . . . . . . . . 59

    312.0 Plumbing Connections . . . . . . . . . . 59

    312.1 General. . . . . . . . . . . . . . . . . . . . . . 59

  • CMC § 303.7 Medium relevance — show source text

    303.7 Liquefied Petroleum Gas (LP-Gas) Facilities . . . . . . . . . . . . . . 53

    303.8 Appliances on Roofs. . . . . . . . . . . . 53

    303.9 Avoiding Strain on Gas Piping . . . . 53

    303.10 Clearance to Combustible

    Materials . . . . . . . . . . . . . . . . . . . . . 53

    303.11 Installation in Commercial

    Garages . . . . . . . . . . . . . . . . . . . . . 54

    303.12 Installation in Aircraft Hangars . . . . 54

    304.0 Accessibility for Service . . . . . . . . . 54

    304.1 General. . . . . . . . . . . . . . . . . . . . . . 54

    304.2 Sloped Roof . . . . . . . . . . . . . . . . . . 54

    304.3 Access to Appliances on Roofs . . . 54

    304.4 Appliances in Attics and Under-Floor Spaces . . . . . . . . . . . . 54

    305.0 Location . . . . . . . . . . . . . . . . . . . . . 55

    305.1 Installation in Residential Garages . . 55

    305.2 Pit Location. . . . . . . . . . . . . . . . . . . 55

    305.3 Flood Hazard Areas . . . . . . . . . . . . 55

    305.4 Elevator Shaft . . . . . . . . . . . . . . . . . 55

    305.5 Drainage Pan . . . . . . . . . . . . . . . . . 55

    305.6 Outdoor Locations . . . . . . . . . . . . . 55

    306.0 Automatic Control Devices . . . . . . . 55

    306.1 General. . . . . . . . . . . . . . . . . . . . . . 55

    306.2 Building Automation Systems . . . . 56

    2025 CALIFORNIA MECHANICAL CODE

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

    TABLE OF CONTENTS

    307.0 Labeling . . . . . . . . . . . . . . . . . . . . . 56

    307.1 Fuel-Burning Appliances . . . . . . . . 56

    307.2 Electric Heating Appliances . . . . . . 56

    307.3 Heat Pump and Electric Cooling Appliances . . . . . . . . . . . . . . . . . . . 56

    307.4 Absorption Units . . . . . . . . . . . . . . . 56

    308.0 Improper Location. . . . . . . . . . . . . . 57

    308.1 General. . . . . . . . . . . . . . . . . . . . . . 57

    309.0 Workmanship . . . . . . . . . . . . . . . . . 57

    309.1 Engineering Practices. . . . . . . . . . . 57

    309.2 Concealing Imperfections . . . . . . . . 57

    309.3 Installation Practices. . . . . . . . . . . . 57

  • CMC § 909.12.4 Medium relevance — show source text

    909.12.4 Automatic control. Where completely automatic control is required or used, the automatic-control sequences shall be initiated from an appropriately zoned automatic sprinkler system complying with Section 903.3.1.1, manual controls provided with ready access for the fire department and any smoke detectors required by the engineering analysis.

    909.13 Control air tubing. Control air tubing shall be of sufficient size to meet the required response times. Tubing shall be flushed clean and dry prior to final connections and shall be adequately supported and protected from damage. Tubing passing through concrete or masonry shall be sleeved and protected from abrasion and electrolytic action.

    909.13.1 Materials. Control air tubing shall be hard drawn copper, Type L, ACR in accordance with ASTM B42, ASTM B43, ASTM B68/B68M, ASTM B88, ASTM B251 and ASTM B280. Fittings shall be wrought copper or brass, solder type, in accordance with ASME B16.18 or ASME B16.22. Changes in direction shall be made with appropriate tool bends. Brass compression-type fittings shall be used at final connection to devices; other joints shall be brazed using a BCuP5 brazing alloy with solidus above 1,100°F (593°C) and liquidus below 1,500°F (816°C). Brazing flux shall be used on copper-to-brass joints only.

    Exception: Nonmetallic tubing used within control panels and at the final connection to devices, provided that all of the following conditions are met:

    1. Tubing shall comply with the requirements of Section 602.3.5 of the California Mechanical Code .
    2. Tubing and the connected device shall be completely enclosed within a galvanized or paint-grade steel enclosure having a minimum thickness of 0.0296 inch (0.7534 mm) (No. 22 gage). Entry to the enclosure shall be by copper tubing with a protective grommet of neoprene or Teflon or by suitable brass compression to male-barbed adapter.
    3. Tubing shall be identified by appropriately documented coding.
    4. Tubing shall be neatly tied and supported within the enclosure. Tubing bridging cabinets and doors or moveable devices shall be of sufficient length to avoid tension and excessive stress. Tubing shall be protected against abrasion. Tubing connected to devices on doors shall be fastened along hinges.

    909.13.2 Isolation from other functions. Control tubing serving other than smoke control functions shall be isolated by automatic isolation valves or shall be an independent system.

    909.13.3 Testing. Control air tubing shall be tested at three times the operating pressure for not less than 30 minutes without any noticeable loss in gauge pressure prior to final connection to devices.

    909.14 Marking and identification. The detection and control systems shall be clearly marked at all junctions, accesses and terminations.

    909.15 Control diagrams. Identical control diagrams showing all devices in the system and identifying their location and function shall be maintained current and kept on file with the fire code official, the fire department and in the fire command center in a format and manner approved by the fire code official.

  • CMC § 150.0 Medium relevance — show source text

    Forward phase cut dimmers controlling LED light sources in these spaces shall comply with NEMA SSL 7A. Exception 1 to Section 150.0(k)2F: Ceiling fans may provide control of integrated lighting via a remote control. Lighting integral to kitchen range hoods and bathroom exhaust fans. Exception 2 to Section 150.0(k)2F: Luminaires connected to a circuit with controlled lighting power less than 20 watts or controlled by an occupancy or vacancy sensor providing automatic-off functionality. Exception 3 to Section 150.0(k)2F: Navigation lighting rated less than 5 watts, such as night lights, step lights, and path lights. Lighting controlled by automatic-off controls and located internal to drawers, cabinetry with opaque fronts, or cabinetry with doors. G. Independent controls. Lighting integrated with the exhaust fans shall be controlled independently from the fans. The following shall be controlled separately from ceiling-installed lighting such that one can be turned on without turning on the other: i. Undercabinet lighting. ii. Undershelf lighting. iii. Interior lighting of display cabinets.

    iv. Switched outlets.

    1. Residential outdoor lighting. In addition to meeting the requirements of Section 150.0(k)1A, luminaires providing residential outdoor lighting shall meet the following requirements, as applicable: A. Outdoor lighting permanently mounted to a residential building or to other buildings on the same lot shall meet the following requirements: i. Controlled by a manual ON and OFF control switch that permits the automatic actions of Item ii below; and ii. Controlled by one of the following controls: a. A photocell and a motion sensor; or b. A photocell and an automatic time switch control; or c. Controlled by an astronomical time clock control. B. Controls that override to ON shall not be allowed unless the override automatically returns the automatic control to its normal operation within 6 hours. C. An energy management control system (EMCS) or other controls that provides the specified lighting control functionality and complies with all requirements applicable to the specified controls may be used to meet these requirements.
    2. Internally illuminated address signs. Internally illuminated address signs shall either: A. Comply with Section 140.8; or B. Consume no more than 5 watts of power.
    3. Residential garages for eight or more vehicles. Lighting for residential parking garages for eight or more vehicles shall comply with the applicable requirements for nonresidential garages in Sections 110.9, 130.0, 130.1, 130.4, 140.6 and 141.0.

    (l) Reserved.

    (m) Air-distribution and ventilation system ducts, plenums and fans.

    1. CMC compliance.

    A. All air-distribution system ducts and plenums, including but not limited to, mechanical closets and air-handler boxes, shall meet the requirements of the CMC Sections 601.0, 602.0, 603.0, 604.0, 605.0 and ANSI/SMACNA-006-2006 HVAC Duct Construction Standards Metal and Flexible, 3rd Edition, incorporated herein by reference.

    2025 CALIFORNIA ENERGY CODE 163

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    SINGLE-FAMILY RESIDENTIAL BUILDINGS— MANDATORY FEATURES AND DEVICES

    B. Portions of supply-air and return-air ducts and plenums of a space heating or cooling system shall be insulated in accordance with either Subsection i or ii below:

Frequently asked questions

What exactly is a “listed device” in § 306.1?

A listed device is equipment that has been tested and listed by an approved testing agency per the appliance or control standard referenced — the code text requires a listed device but does not restate which listing body; follow the appliance manufacturer/listing and AHJ. § 306.1 .

If my BAS uses a resilient IP network with automatic failover, do I still need local controls?

Yes. § 306.2 requires that the BAS “provide for localized control in the event of network failure” and that the capability be specified in the construction documents, regardless of network redundancy. § 306.2 .

Are kitchen ranges required to have the listed shutoff devices in § 306.1?

No. The exception in § 306.1 specifically excludes ranges, cooking tops, log lighters, lights, or other open‑burner manually operated appliances from the listed‑shutoff requirement. § 306.1 .

How should the localized control be documented?

The code requires the localized‑control capability to be specified in the construction documents (plans, specifications, or narrative). The code text does not prescribe exact wording or format — provide clear drawings and a written description of how local control operates and when it is used. § 306.2 .

If a furnace’s listing locates the outlet temperature control differently, which governs?

Follow the appliance listing or the code location requirement; § 306.1 allows the control to be located “in accordance with the conditions of listing” when applicable. § 306.1 .

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