CMC · California Mechanical Code

What are inspection, operating permit, and inspection-frequency requirements?

You must have an AHJ inspection and an operating permit before running boilers or pressure vessels; the CMC sets minimum inspection frequencies (annual or biennial depending on equipment) and lets the AHJ or ASHRAE/ACCA 180 require more frequent checks.

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

Boilers and pressure vessels that require a permit may not be put into service until inspected and approved by the Authority Having Jurisdiction under § 1013.1. An operating permit is required before operation (and must be posted at the equipment) under § 1013.2. The AHJ must perform maintenance inspections in accordance with ASHRAE/ACCA 180 and at intervals not less frequent than the schedules in § 1013.4 through § 1013.7.

The single most important rule: you cannot put a permitted boiler or pressure vessel into service or operate it without inspection and an operating permit approved by the Authority Having Jurisdiction.

Requirements in detail

Who inspects, and when inspections are required

  • Before initial use: an installation for which a permit is required shall not be placed into service until inspected and approved by the Authority Having Jurisdiction (§ 1013.1) — the owner must notify the AHJ that the installation is ready for inspection and post a conspicuous “not yet inspected” notice until approval.
  • Operating permit prerequisite: a valid operating permit must be obtained before operating a boiler or pressure vessel; the permit must be displayed adjacent to the equipment and will not be issued until the AHJ has inspected and approved the equipment (§ 1013.2). Exception: certain small residential and utility occupancies are exempt (see § 1013.2).
  • Maintenance inspections: the AHJ shall inspect permitted equipment in accordance with ASHRAE/ACCA 180 at intervals the AHJ deems necessary but not less frequently than the schedules in the following sections (§ 1013.3).

Inspection-frequency schedule (decision table)

Equipment type External inspection frequency Internal inspection frequency (when permitted/possible) Code Reference
Power boilers and miniature boilers Annually Annually where construction/operating conditions permit § 1013.4
Steam‑heating boilers and hot‑water‑heating boilers Annually Annually where construction/operating conditions permit § 1013.5
Automatic steam‑heating boilers Biennially (every 2 years) Biennially where construction/operating conditions permit § 1013.6
Unfired pressure vessels Biennially Biennially where subject to corrosion and construction permits § 1013.7

Notes:

  • “Annually” = once every 12 months; “Biennially” = once every 24 months, per the plain language of the sections above.
  • The AHJ may require more frequent inspection consistent with ASHRAE/ACCA 180 and local authority determination (§ 1013.3).

Permit, inspection records, and third‑party inspectors

  • The AHJ may permit insurance-company inspectors (holding National Board commissions) to perform inspections on behalf of the AHJ; such inspectors must file prescribed reports with the AHJ and notify the AHJ of insurance suspensions or changes. This reporting/approval requirement is in the same inspection chapter.

Exceptions & special cases

  • Residential and utility exemption: operation of steam‑heating boilers, low‑pressure hot‑water‑heating boilers, hot‑water supply boilers, and pressure vessels in residential occupancies of less than six dwelling units and utility occupancies are excepted from the operating‑permit requirement in § 1013.2. Check the AHJ for how they interpret “utility occupancies.”
  • Registered design professional alternative: when an installation is designed and supervised by a registered design professional, the AHJ may allow that professional to perform inspection and testing in lieu of the AHJ’s direct inspection per § 1013.1.
  • Construction/operating conditions qualifier: internal inspection frequencies are qualified by “where construction and operating conditions permit,” meaning physical access or equipment design may limit internal inspection—coordinate with the AHJ to determine feasibility under § 1013.4–§ 1013.7.

Common mistakes

  • Assuming “permit = final paperwork only.” The operating permit will not be issued until the equipment is inspected and approved by the AHJ (§ 1013.2). Don’t start operation before inspection and permit are in place.
  • Treating the table frequencies as optional maxima. The AHJ can require more frequent inspections following ASHRAE/ACCA 180; the code sets minimum frequencies, not ceilings (§ 1013.3).
  • Forgetting to post the required warning/permit notice. The owner must post the “not yet inspected” warning until inspection approval under § 1013.1, and the operating permit must be displayed adjacent to the boiler or vessel under § 1013.2.
  • Relying on insurer inspection without AHJ approval. Insuring‑company inspectors must be approved by the AHJ and must submit reports to the AHJ—insurer inspection does not supplant AHJ approval unless accepted by the AHJ.

Worked example — concrete scenario

Scenario: A small apartment building contains (A) one 150‑psi power boiler and (B) one automatic steam‑heating boiler. The owner wishes to know inspection and permit timing.

Step 1 — Permit and initial inspection:

  • Both boilers require a permit and the owner must notify the AHJ and post the “not yet inspected” notice. Neither boiler may be placed into service until inspected and approved per § 1013.1. The operating permit must then be obtained and displayed per § 1013.2.

Step 2 — Maintenance inspection schedule:

  • The power boiler (A) triggers annual external inspection and, if feasible, annual internal inspection under § 1013.4 (so expect at least one external inspection every 12 months).
  • The automatic steam‑heating boiler (B) is inspected externally biennially (every 24 months) and internally biennially where conditions permit, per § 1013.6.

Step 3 — AHJ discretion and ASHRAE/ACCA 180:

  • The AHJ may adopt ASHRAE/ACCA 180 intervals or require more frequent checks than the table minima. If the AHJ follows ASHRAE/ACCA 180 and that standard calls for, say, annual maintenance for the automatic steam boiler in that service condition, the AHJ can require annual inspections even though § 1013.6 sets a biennial minimum. Always confirm with the AHJ because § 1013.3 allows the AHJ to inspect “at such intervals as deemed necessary” while not going below the table minima.

Related provisions

  • § 1012.1 — Operating adjustments and instructions (controls and operating instructions required on completion).
  • § 1014.1 — Operation and maintenance; AHJ authority to notify owners of defects and revoke permits for unsafe operation.
  • § 105.1 — General inspection rules for mechanical systems (scheduling and prohibition on concealment before inspection).
  • § 514.2 — Related inspection/testing/maintenance provisions for kitchen exhaust/fire‑extinguishing systems (inspection frequency and certification/records).

Code references

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

  • CMC § 1013.2 High relevance — show source text

    Where the owner or his authorized representative requests inspection of a boiler prior to its installation, the Authority Having Jurisdiction shall make such inspection. 1013.2 Operating Permit. It shall be unlawful to operate a boiler or pressure vessel without first obtaining a valid operating permit to do so from the Authority Having Jurisdiction. Such permit shall be displayed in a conspicuous place adjacent to the boiler or vessel. The operating permit shall not be issued until the equipment has been inspected and approved by the Authority Having Jurisdiction.

    Exception: The operation of steam-heating boilers, low-pressure hot-water-heating boilers, hot water supply boilers, and pressure vessels in residential occupancies of less than six dwelling units and utility occupancies. 1013.3 Maintenance Inspection. The Authority Having Jurisdiction shall inspect boilers and pressure vessels operated under a permit in accordance with ASHRAE/ACCA 180 at such intervals as deemed necessary, but not less frequently than in accordance with Section 1013.4 through Section 1013.7.

    1013.4 Power and Miniature Boilers. Power boilers and miniature boilers shall be inspected externally annually. Where construction and operating conditions permit, they shall be subject to inspection internally annually. 1013.5 Steam-Heating and Water-Heating Boilers. Steam-heating boilers and hot-water-heating boilers shall be inspected externally annually. Where construction and operating conditions permit, they shall also be subject to inspection internally annually. 1013.6 Automatic Steam-Heating Boilers. Automatic steam-heating boilers shall be inspected externally biennially. Where construction and operating conditions permit, they shall be subject to inspection internally biennially. 1013.7 Unfired Pressure Vessels. Unfired pressure vessels shall be inspected externally biennially. Where subject to corrosion and construction permits, they shall be subject to inspection internally biennially.

    Inspection of boilers and pressure vessels covered by insurance shall be permitted to be made by employees of the insuring company holding commissions from the National Board of Boiler and Pressure Vessel Inspectors, subject to approval of the Authority Having Jurisdiction. Approved insuring company inspectors shall make reports on prescribed forms on inspections authorized by the Authority Having Jurisdiction. The reports shall be filed in the Authority Having Jurisdiction office. Company inspectors shall notify the Authority Having Jurisdiction of suspension of insurance because of dangerous conditions, new insurance in effect, and discontinuance of insurance

    coverage.

    1014.0 Operation and Maintenance of Boilers and Pressure Vessels.

    1014.1 General. Boilers and pressure vessels shall be operated and maintained in accordance with requirements for pro

    tection of the public established by the Authority Having Jurisdiction in accordance with nationally recognized standards.

    The Authority Having Jurisdiction shall notify the owner or authorized representative of defects or deficiencies and properly corrected. Where such corrections are not made, or where the operation of the boiler or pressure vessel is deemed unsafe by the Authority Having Jurisdiction, they shall have the authority to revoke the permit to operate the boiler or pressure vessel. Where the operation of a boiler or pressure vessel is deemed by the Authority Having Jurisdiction to constitute an immediate danger, the pressure on such boiler or pressure vessel shall be permitted to be relieved at the owner’s cost and the boiler or pressure vessel shall not thereafter be operated without the approval of the Authority Having Jurisdiction.

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  • CMC § 1012.0 High relevance — show source text

    1012.0 Operating Adjustments and Instructions. 1012.1 General. Hot water boiler installations, upon completion, shall have controls set, adjusted, and tested by the installing contractor. A complete control diagram of a permanent legible type, together with complete boiler operating instructions, shall be furnished by the installer for each installation.

    1013.0 Inspections and Tests. 1013.1 General. An installation for which a permit is required shall not be put into service until it has been inspected and approved by the Authority Having Jurisdiction.

    It shall be the duty of the owner or his authorized representative to notify the Authority Having Jurisdiction that the installation is ready for inspection and test. It also shall be the duty of the owner or his authorized representative to post in a conspicuous position on the installation a notice in substantially the following form: “WARNING! THIS INSTALLATION HAS NOT BEEN INSPECTED AND APPROVED

    BY THE AUTHORITY HAVING JURISDICTION AND

    SHALL NOT BE COVERED OR CONCEALED UNTIL SO INSPECTED AND APPROVED,” and it shall be unlawful for anyone other than the Authority Having Jurisdiction to remove such notice. The Authority Having Jurisdiction shall require such tests as it deems necessary to determine that the installation is in accordance with the provision of this section. Such tests shall be made by the owner or his authorized representative in the presence of the Authority Having Jurisdiction.

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    BOILERS AND PRESSURE VESSELS

    Exception: On installations designed and supervised by a registered design professional, the Authority Having Jurisdiction shall have the authority to permit inspection and testing by such registered design professional.

    Where the owner or his authorized representative requests inspection of a boiler prior to its installation, the Authority Having Jurisdiction shall make such inspection. 1013.2 Operating Permit. It shall be unlawful to operate a boiler or pressure vessel without first obtaining a valid operating permit to do so from the Authority Having Jurisdiction. Such permit shall be displayed in a conspicuous place adjacent to the boiler or vessel. The operating permit shall not be issued until the equipment has been inspected and approved by the Authority Having Jurisdiction.

    Exception: The operation of steam-heating boilers, low-pressure hot-water-heating boilers, hot water supply boilers, and pressure vessels in residential occupancies of less than six dwelling units and utility occupancies. 1013.3 Maintenance Inspection. The Authority Having Jurisdiction shall inspect boilers and pressure vessels operated under a permit in accordance with ASHRAE/ACCA 180 at such intervals as deemed necessary, but not less frequently than in accordance with Section 1013.4 through Section 1013.7.

    1013.4 Power and Miniature Boilers. Power boilers and miniature boilers shall be inspected externally annually. Where construction and operating conditions permit, they shall be subject to inspection internally annually. 1013.5 Steam-Heating and Water-Heating Boilers. Steam-heating boilers and hot-water-heating boilers shall be inspected externally annually. Where construction and operating conditions permit, they shall also be subject to inspection internally annually. 1013.6 Automatic Steam-Heating Boilers. Automatic steam-heating boilers shall be inspected externally biennially. Where construction and operating conditions permit, they shall be subject to inspection internally biennially.

  • CMC § 104.5.2 High relevance — show source text

    ** Where work for which a permit is required by this code has been commenced without first obtaining said permit, a special investigation shall be made before a permit is issued for such work. 104.5.2 Investigation Fees. An investigation fee, in addition to the permit fee, shall be collected whether a permit is then or subsequently issued. The investigation fee shall be equal to the amount of the permit fee that is required by this code if a permit were to be issued. The payment of such investigation fee shall not exempt a person from compliance with other provisions of this code, nor from a penalty prescribed by law. 104.5.3 Fee Refunds. The Authority Having Jurisdiction shall be permitted to authorize the refunding of a fee as follows:

    (1) The amount paid hereunder that was erroneously paid or collected.

    (2) Refunding of not more than a percentage, as determined by this jurisdiction where no work has been done under a permit issued in accordance with this code.

    The Authority Having Jurisdiction shall not authorize the refunding of a fee paid except upon written application filed by the original permittee not to exceed 180 days after the date of fee payment.

    105.0 Inspections and Testing.

    105.1 General. Plumbing systems for which a permit is required by this code shall be inspected by the Authority Having Jurisdiction.

    No plumbing system or portion thereof shall be covered, concealed, or put into use until inspected and approved as prescribed in this code. Neither the Authority Having Jurisdiction nor the jurisdiction shall be liable for expense entailed in the removal or replacement of material required to permit inspection. Plumbing systems regulated by this code shall not be connected to the water, the energy fuel supply, or the sewer system until authorized by the Authority Having Jurisdiction.

    105.2 Required Inspections. New plumbing work and such portions of existing systems as affected by new work, or changes, shall be inspected by the Authority Having Jurisdiction to ensure compliance with the requirements of this code and to ensure that the installation and construction of the plumbing system are in accordance with approved plans. The Authority Having Jurisdiction shall make the following inspections and other such inspections as necessary. The permittee or the permittee’s authorized agent shall be responsible for the scheduling of such inspections as follows:

    (1) The underground inspection shall be made after trenches or ditches are excavated and bedded, piping installed, and before backfill is put in place.

    (2) Rough-in inspection shall be made prior to the installation of wall or ceiling membranes.

    (3) Final inspection shall be made upon completion of the installation.

    105.2.1 Uncovering. Where a drainage or plumbing system, building sewer, private sewage disposal system, or part thereof, which is installed, altered, or repaired, is covered or concealed before being inspected, tested, and approved as prescribed in this code, it shall be uncovered for inspection after notice to uncover the work has been issued to the responsible person by the Authority Having Jurisdiction.

    The requirements of this section shall not be considered to prohibit the operation of plumbing installed to replace existing equipment or fixtures serving an occupied portion of the building in the event a request for inspection of such equipment or fixture has been filed with the Authority Having Jurisdiction not more than 72 hours after such replacement work is completed, and before a portion of such plumbing system is concealed by a permanent portion of the building.

    105.2.1.1 Water Supply System. No water supply system or portion thereof shall be covered or concealed until it first has been tested, inspected, and approved.

  • CMC § 403.3.1.1 Medium relevance — show source text

    Spaces in which such systems are located shall be considered to be kitchens and shall be ventilated in accordance with Table 403.3.1.1 of the California Mechanical Code . For the purpose of determining the floor area required to be ventilated, each individual appliance shall be considered as occupying not less than 100 square feet (9.3 m [2] ). 3. Where cooking appliances are equipped with integral down-draft exhaust systems and such appliances and exhaust systems are listed and labeled for the application in accordance with NFPA 96, a hood shall not be required at or above them.

    1. A Type I hood shall not be required for an electric cooking appliance where an approved testing agency provides documentation that the appliance effluent contains 5 mg/m [3] or less of grease when tested at an exhaust flow rate of 500 cfm (0.236 m [3] /s) in accordance with UL 710B.

    606.3 Operations and maintenance. Commercial cooking systems shall be operated, inspected and maintained in accordance with Sections 606.3.1 through 606.3.4.

    606.3.1 Ventilation system. The ventilation system in connection with hoods shall be operated at the required rate of air movement, and grease filters listed and labeled in accordance with UL 1046 shall be in place where equipment under a kitchen grease hood is used.

    606.3.2 Grease extractors. Where grease extractors are installed, they shall be operated when the commercial-type cooking equipment is used.

    606.3.3 Cleaning. Hoods, grease-removal devices, fans, ducts and other appurtenances shall be cleaned at intervals as required by Sections 606.3.3.1 through 606.3.3.3.

    606.3.3.1 Inspection. Hoods, grease-removal devices, fans, ducts and other appurtenances shall be inspected at intervals specified in Table 606.3.3.1 or as approved by the fire code official. Inspections shall be completed by qualified individuals.

    TABLE 606.3.3.1—COMMERCIAL COOKING SYSTEM INSPECTION FREQUENCY Col2
    TYPE OF COOKING OPERATIONS FREQUENCY OF INSPECTION
    High-volume cooking operations such as 24-hour cooking, charbroiling or wok cooking 3 months
    Low-volume cooking operations such as places of religious worship, seasonal businesses and senior centers 12 months
    Cooking operations utilizing solid fuel-burning cooking appliances 1 month
    All other cooking operations 6 months

    606.3.3.2 Grease accumulation. If during the inspection it is found that hoods, grease-removal devices, fans, ducts or other appurtenances have an accumulation of grease, such components shall be cleaned in accordance with ANSI/IKECA C10.

    606.3.3.3 Records. Records for inspections shall state the individual and company performing the inspection, a description of the inspection and when the inspection took place. Records for cleanings shall state the individual and company performing the cleaning and when the cleaning took place. Such records shall be completed after each inspection or cleaning and maintained.

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    BUILDING SERVICES AND SYSTEMS

  • CMC § 1401.0 Medium relevance — show source text

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    CHAPTER 14

    PROCESS PIPING

    1401.0 General.

    1401.1 Applicability. Except as otherwise addressed in this code, this chapter shall govern the installation of process piping in or in conjunction with a building or structure located upon the premises.

    1402.0 Permit.

    1402.1 General. It shall be unlawful to install, alter, or repair or cause to be installed, altered, or repaired process material piping without first obtaining a permit.

    Permits for process piping shall show the total number of outlets to be provided for on each system and such other information as required by the Authority Having Jurisdiction.

    Fees for process piping permits are included in Table 104.5.

    1403.0 Plans Required.

    1403.1 General. Plans, engineering calculations, diagrams, and other data shall be submitted in one or more sets with each application for a permit. The Authority Having Jurisdiction shall be permitted to require plans, computations, and specifications to be prepared and designed by a registered design professional.

    Where plans or other data are submitted for review, a plan review fee shall be paid, as provided in Section 104.3.2.

    1404.0 Workmanship.

    1404.1 General. Process piping shall not be strained or bent, nor shall tanks, vessels, vats, appliances, or cabinets be supported by or develop strain or stress on the piping.

    1405.0 Inspections.

    1405.1 General. Upon completion of the installation, alteration, or repair of process piping, and prior to the use thereof, the Authority Having Jurisdiction shall be notified that such piping is ready for inspection.

    Excavations required for the installation of underground piping shall be kept open until such time as the piping has been inspected and approved. Where such piping is covered or concealed before such approval, it shall be exposed upon the direction of the Authority Having Jurisdiction.

    1405.2 Required Inspections. The Authority Having Jurisdiction shall make the following inspections and shall either approve that portion of the work as completed or shall notify the permit holder wherein the same fails to be in accordance with this code.

    1405.2.1 Rough Piping Inspection. This inspection shall be made after process piping authorized by the permit has been installed and before piping has been cov

    ered or concealed. This inspection shall include a determination that the piping size, material, and installation are in accordance with the requirements of this code.

    1405.2.2 Final Piping Inspection. This inspection shall be made after piping authorized by the permit has been installed and after portions thereof that are to be covered or concealed are so concealed. This inspection shall include a pressure test, at which time the piping shall stand a pressure of not less than one-and-one-half times the maximum designed operating pressure where hydraulic testing is conducted or 110 percent where testing is conducted pneumatically. Test pressures shall be held for a length of time satisfactory to the Authority Having Jurisdiction, but in no case for less than 30 minutes with no perceptible drop in pressure. HPM drain, waste, and vent piping shall be tested in accordance with the plumbing code. Tests shall be made in the presence of the Authority Having Jurisdiction. Necessary apparatus for conducting tests shall be furnished by the permit holder.

  • CMC § 1601.5 Medium relevance — show source text

    TABLE 1601.5 MINIMUM ALTERNATE WATER SOURCE TESTING, INSPECTION, AND MAINTENANCE FREQUENCY

    DESCRIPTION MINIMUM FREQUENCY



    Inspect and clean filters and
    screens, and replace (where
    necessary).    		 Every 3 months






    Inspect and verify that
    disinfection, filters, and water
    quality treatment devices and
    systems are operational and
    maintaining minimum water
    quality requirements as
    determined by the Authority
    Having Jurisdiction.    		 In accordance with manufac-
    turer’s instructions and the
    Authority Having Jurisdiction.



    Inspect and clear debris from
    rainwater gutters, downspouts,
    and roof washers.    		 Every 6 months




    Inspect and clear debris from
    the roof or another above-
    ground rainwater collection
    surfaces.    		 Every 6 months




    Remove tree branches and
    vegetation overhanging a roof
    or other aboveground rainwater
    collection surfaces.    		 As needed


    Inspect pumps and verify
    operation.    		 After initial installation and
    every 12 months thereafter


    Inspect valves and verify
    operation.    		 After initial installation and
    every 12 months thereafter


    Inspect pressure tanks and
    verify operation.    		 After initial installation and
    every 12 months thereafter


    Clear debris from and inspect
    storage tanks, locking devices,
    and verify operation.    		 After initial installation and
    every 12 months thereafter


    Inspect caution labels and
    marking.    		 After initial installation and
    every 12 months thereafter


    Cross-connection inspection
    and test.*    		 After initial installation and
    every 12 months thereafter




    Test water quality of rainwater
    catchment systems required by
    Section 1603.4 to maintain a
    minimum water quality.    		 Every 12 months. After system
    renovation or repair.
    • The cross-connection test shall be performed in the presence of the Authority Having Jurisdiction in accordance with the requirements of this chapter.

    1601.5.1 Maintenance Responsibility. The required maintenance and inspection of rainwater catchment systems shall be the responsibility of the property owner unless otherwise required by the Authority Having Jurisdiction.

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    NONPOTABLE RAINWATER CATCHMENT SYSTEMS

    1601.6 Operation and Maintenance Manual. An operation and maintenance manual for rainwater catchment systems required to have a permit in accordance with Section 1601.3, shall be supplied to the building owner by the system designer or installer . The operating and maintenance manual shall include the following:

    (1) Diagram(s) of the entire system and the location of system components.

    (2) Instructions for operating and maintaining the system.

    (3) Instructions on maintaining the required water quality as for rainwater catchment systems .

  • CMC § 104.4.6 Medium relevance — show source text

    104.4.6 Retention of Plans. One set of approved construction documents and computations shall be retained by the Authority Having Jurisdiction until final approval of the work is covered therein.

    One set of approved construction documents, computations, and manufacturer’s installation instructions shall be returned to the applicant, and said set shall be kept on the site of the building or work at times during which the work authorized thereby is in progress.

    104.5 Fees. Fees shall be assessed in accordance with the provisions of this section and as set forth in the fee schedule, Table 104.5. The fees are to be determined and adopted by this jurisdiction. 104.5.1 Work Commencing Before Permit Issuance. Where work for which a permit is required by this code has been commenced without first obtaining said permit, a special investigation shall be made before a permit is issued for such work. 104.5.2 Investigation Fees. An investigation fee, in addition to the permit fee, shall be collected whether or not a permit is then or subsequently issued. The investigation fee shall be equal to the amount of the permit fee

    that is required by this code if a permit were to be issued. The payment of such investigation fee shall not exempt a person from compliance with other provisions of this code, nor from a penalty prescribed by law. 104.5.3 Fee Refunds. The Authority Having Jurisdiction shall be permitted to authorize the refunding of a fee as follows:

    (1) The amount paid hereunder that was erroneously paid or collected.

    (2) Refunding of not more than a percentage, as determined by this jurisdiction where no work has been done under a permit issued in accordance with this code.

    The Authority Having Jurisdiction shall not authorize refunding of a fee paid except upon written application filed by the original permittee not to exceed 180 days after the date of fee payment.

    105.0 Inspections and Testing. 105.1 General. Mechanical systems for which a permit is required by this code shall be inspected by the Authority Having Jurisdiction.

    No mechanical system or portion thereof shall be covered, concealed, or put into use until inspected and approved as prescribed in this code. Neither the Authority Having Jurisdiction nor the jurisdiction shall be liable for expense entailed in the removal or replacement of material required to permit inspection. Mechanical systems regulated by this code shall not be connected to the energy fuel supply lines until authorized by the Authority Having Jurisdiction.

    105.2 Required Inspections. New mechanical system work and such portions of existing systems as affected by new work, or changes, shall be inspected by the Authority Having Jurisdiction to ensure compliance with the requirements of this code and to ensure that the installation and construction of the mechanical system are in accordance with approved plans. The Authority Having Jurisdiction shall make the following inspections and other such inspections as necessary. The permittee or the permittee’s authorized agent shall be responsible for the scheduling of such inspections as follows:

    (1) Underground inspection shall be made after trenches or ditches are excavated and bedded, piping installed, and before backfill is put in place.

    (2) Rough-in inspection shall be made prior to the installation of wall or ceiling membranes.

    (3) Final inspection shall be made upon completion of the installation.

  • CMC § 101.5.1 Medium relevance — show source text

    K 101.5.1 Frequency. Potable rainwater catchment systems and components shall be inspected and maintained in accordance with Table K 101.5.1 unless more

    frequent inspection and maintenance are required by the manufacturer.

    K 101.5.2 Maintenance Log. A maintenance log for potable rainwater catchment systems shall be maintained by the property owner and be available for inspection. The property owner or designated appointee shall ensure that a record of testing, inspection, and maintenance in accordance with Table K 101.5.1 is maintained in the log. The log will indicate the frequency of inspection, and maintenance of each system. A record of the required water quality tests shall be retained for not less than 2 years.

    K 101.5.3 Maintenance Responsibility. The required maintenance and inspection of potable rainwater catchment systems shall be the responsibility of the property owner unless otherwise required by the Authority Having Jurisdiction.

    K 101.6 Operation and Maintenance Manual. An operation and maintenance manual for potable rainwater catchment systems shall be supplied to the building owner by the system designer. The operating and maintenance manual shall include the following:

    (1) Detailed diagram of the entire system and the location of system components.

    (2) Instructions for operating and maintaining the system.

    (3) Details on maintaining the required water quality as determined by the Authority Having Jurisdiction.

    (4) Details on deactivating the system for maintenance, repair, or other purposes.

    (5) Applicable testing, inspection, and maintenance frequencies in accordance with Table K 101.5.1.

    (6) A method of contacting the manufacturer(s).

    K 101.7 Minimum Water Quality Requirements. The minimum water quality for potable rainwater catchment systems shall comply with the applicable water quality requirements as determined by the Authority Having Jurisdiction. In the absence of water quality requirements, the guidelines EPA/600/R12/618 contains recommended water reuse guidelines to assist regulatory agencies develop, revise, or expand alternate water source water quality standards.

    K 101.8 Material Compatibility. In addition to the requirements of this appendix, potable rainwater catchment systems shall be constructed of materials that are compatible with the type of pipe and fitting materials and water conditions in the system.

    K 101.9 System Controls. Controls for pumps, valves, and other devices that contain mercury that come in contact with the water supply shall not be permitted.

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    APPENDIX K

    TABLE K 101.5.1 MINIMUM POTABLE RAINWATER CATCHMENT SYSTEM TESTING, INSPECTION, AND MAINTENANCE FREQUENCY

    DESCRIPTION MINIMUM FREQUENCY
    Inspect and clean filters and screens, and replace (where necessary). Every 3 months
    Inspect and verify that disinfection, filters and water quality treatment devices and
    systems are operational. Perform water quality tests in accordance with the Author-
    ity Having Jurisdiction.    		 In accordance with the manufacturer’s instructions,
    and the Authority Having Jurisdiction.
    Perform applicable water quality tests to verify compliance with Section K 104.3. Every 3 months
    Perform a water quality test for E. Coli, Total Coliform, and Heterotrophic bacte-
    ria.
  • CMC § 1405.2 Medium relevance — show source text

    Excavations required for the installation of underground piping shall be kept open until such time as the piping has been inspected and approved. Where such piping is covered or concealed before such approval, it shall be exposed upon the direction of the Authority Having Jurisdiction.

    1405.2 Required Inspections. The Authority Having Jurisdiction shall make the following inspections and shall either approve that portion of the work as completed or shall notify the permit holder wherein the same fails to be in accordance with this code.

    1405.2.1 Rough Piping Inspection. This inspection shall be made after process piping authorized by the permit has been installed and before piping has been cov

    ered or concealed. This inspection shall include a determination that the piping size, material, and installation are in accordance with the requirements of this code.

    1405.2.2 Final Piping Inspection. This inspection shall be made after piping authorized by the permit has been installed and after portions thereof that are to be covered or concealed are so concealed. This inspection shall include a pressure test, at which time the piping shall stand a pressure of not less than one-and-one-half times the maximum designed operating pressure where hydraulic testing is conducted or 110 percent where testing is conducted pneumatically. Test pressures shall be held for a length of time satisfactory to the Authority Having Jurisdiction, but in no case for less than 30 minutes with no perceptible drop in pressure. HPM drain, waste, and vent piping shall be tested in accordance with the plumbing code. Tests shall be made in the presence of the Authority Having Jurisdiction. Necessary apparatus for conducting tests shall be furnished by the permit holder.

    1405.3 Other Inspections. In addition to the inspections required by this section, the Authority Having Jurisdiction shall be permitted to require a special inspector, as specified in the building code, during installation of piping systems. In cases where the work authorized was installed in accordance with plans and specifications prepared by a registered design professional, the Authority Having Jurisdiction shall be permitted to require a final signed report stating that the work was installed in accordance with approved plans and specifications and the applicable provisions of this chapter.

    1406.0 Pipe, Tubing, and Fittings.

    1406.1 General. Process pipe, tubing, and fittings shall comply with ASME B31.3 and shall be installed in accordance with the manufacturer’s installation instructions. Materials shall be rated for the operating temperatures and pressures of the system, and shall be compatible with the type of liquid.

    1406.2 Hazardous Process Piping (HPP). HPP supply piping or tubing in service corridors shall be exposed to view. HPP piping shall be identified in accordance with nationally recognized standards to indicate the material being transported. Liquid HPP piping shall have an approved means for directing spilled materials to an approved containment or drainage system.

    Liquid HPP waste or drainage systems shall be installed in accordance with the plumbing code.

    1406.2.1 Installation in Exit Corridors and Above Other Occupancies. Hazardous process supply pipe shall not be located within exit corridors, within a portion of a means of egress required to be enclosed in fire-resistive construction, or in concealed spaces in or above

    2025 CALIFORNIA MECHANICAL CODE 335

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

    PROCESS PIPING

    areas not classified as Group H Occupancies, except as permitted by this subsection.

  • CMC § 108.3 Medium relevance — show source text

    [A] 108.3 Permit valuations. The applicant for a permit shall provide an estimated value of the work for which the permit is being issued at time of application. Such estimated valuations shall include the total value of work, including materials and labor, for which the permit is being issued. Where, in the opinion of the applicable governing authority, the valuation is underestimated, the permit shall be denied, unless the applicant can show detailed estimates acceptable to the applicable governing authority. The applicable governing authority shall have the authority to adjust the final valuation for permit fees.

    [A] 108.4 Work commencing before permit issuance. Any person who commences any work before obtaining the necessary permits shall be subject to a fee established by the applicable governing authority, which shall be in addition to the required permit fees.

    [A] 108.5 Related fees. The payment of the fee for the construction, alteration, removal or demolition of work done in connection to or concurrently with the work or activity authorized by a permit shall not relieve the applicant or holder of the permit from the payment of other fees that are prescribed by law.

    [A] 108.6 Refunds. The applicable governing authority is authorized to establish a refund policy.

    2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE 1-21

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

    ADMINISTRATION

    SECTION 109—INSPECTION AND ENFORCEMENT

    [A] 109.1 Inspection. Inspections shall be in accordance with Sections 109.1.1 through 109.1.4.3.

    [A] 109.1.1 General. Construction or work for which a permit is required by this code shall be subject to inspection by the code official and such construction or work shall remain visible and able to be accessed for inspection purposes until approved by the code official.

    It shall be the duty of the permit applicant to cause the work to remain visible and able to be accessed for inspection purposes. Neither the code official nor the jurisdiction shall be liable for expense entailed in the removal or replacement of any material required to allow inspection.

    Approval as a result of an inspection shall not be construed to be an approval of a violation of the provisions of this code or of other ordinances of the jurisdiction. Inspections presuming to give authority to violate or cancel the provisions of this code or of other ordinances of the jurisdiction shall not be valid.

    Where required by the code official, a survey of the lot shall be provided to verify that the mitigation features are provided and the building or structure is located in accordance with the approved plans.

    [A] 109.1.2 Authority to inspect. The code official shall inspect, as often as necessary, buildings and premises, including such other hazards or appliances designated by the code official for the purpose of ascertaining and causing to be corrected any conditions that could reasonably be expected to cause fire or contribute to its spread, or any violation of the purpose of this code and of any other law or standard affecting fire safety.

    [A] 109.1.2.1 Approved inspection agencies. The code official is authorized to accept reports of approved inspection agencies, provided that such agencies satisfy the requirements as to qualifications and reliability.

  • CMC § 0.120 Medium relevance — show source text

    fastener**
    horizontal spacing| |CLADDING FASTENER
    THROUGH FOAM
    SHEATHING INTO:|CLADDING FASTENER
    TYPE AND MINIMUM SIZEc|CLADDING FASTENER
    VERTICAL SPACING
    (INCHES)|Cladding weight:|Cladding weight:|Cladding weight:|Cladding weight:|Cladding weight:|Cladding weight:|Cladding weight:|Cladding weight:| |CLADDING FASTENER
    THROUGH FOAM
    SHEATHING INTO:|CLADDING FASTENER
    TYPE AND MINIMUM SIZEc|CLADDING FASTENER
    VERTICAL SPACING
    (INCHES)|**3 **
    psf|11
    psf|18
    psf|25
    psf|**3 **
    psf|11
    psf|18
    psf|25
    psf| |Wood Framing
    (minimum 11/4- inch
    penetration)b|0.120" diameter nail|6|3.00|1.70|0.90|0.55|3.00|1.05|0.50|DR| |Wood Framing
    (minimum 11/4- inch
    penetration)b|0.120" diameter nail|8|3.00|1.20|0.60|DR|3.00|0.70|DR|DR| |Wood Framing
    (minimum 11/4- inch
    penetration)b|0.120" diameter nail|12|3.00|0.70|DR|DR|2.15|DR|DR|DR| |Wood Framing
    (minimum 11/4- inch
    penetration)b|0.131" diameter nail|6|4.00|2.15|1.20|0.75|4.00|1.35|0.70|DR| |Wood Framing
    (minimum 11/4- inch
    penetration)b|0.131" diameter nail|8|4.00|1.55|0.80|DR|4.00|0.90|DR|DR| |Wood Framing
    (minimum 11/4- inch
    penetration)b|0.131" diameter nail|12|4.00|0.90|DR|DR|2.70|0.50|DR|DR| |Wood Framing
    (minimum 11/4- inch
    penetration)b|0.162" diameter nail|6|4.00|3.55|2.05|1.40|4.00|2.25|1.25|0.80| |Wood Framing
    (minimum 11/4- inch
    penetration)b|0.162" diameter nail|8|4.00|2.55|1.45|0.95|4.00|1.60|0.85|0.50| |Wood Framing
    (minimum 11/4- inch
    penetration)b|0.162" diameter nail|12|4.00|1.60|0.85|0.50|4.00|0.95|DR|DR| |For SI: 1 inch = 25.

  • CMC § 1501.3 Medium relevance — show source text

    1501.3 Permit. [BSC-CG, HCD 1 & DWR] It shall be unlawful for a person to construct, install, alter, or cause to be constructed, installed, or altered an alternate water source system in a building or on its premise s without first obtaining a permit to do such work from the Authority Having Jurisdiction. No changes or connections shall be made to either the alternate water source system or the potable water system within a site containing an alternate water source system without approval by the Authority Having Jurisdiction. Exception: [BSC-CG & HCD 1] A construction permit shall not be required for a clothes washer system meeting the requirements of Section 1503.1.1. 1501.4 Component Identification. System components shall be properly identified as to the manufacturer. 1501.5 Maintenance and Inspection. [BSC-CG, HCD 1 & DWR] Alternate water source systems and components shall be inspected and maintained in accordance with the

    manufacturer’s recommendations and/or as required by the Authority Having Jurisdiction. [BSC-CG] Where no manu- facturer’s recommendations exist, additional recommenda- tions are listed in Table 1501.5 .

    Exception: [DWR] Recycled water supply systems that are within or a part of a building shall comply with Section 1505.16 .

    1501.5.1 Maintenance Responsibility. The required maintenance and inspection of alternate water source systems shall be the responsibility of the property owner unless otherwise required by the Authority Having Jurisdiction.

    1501.6 Operation and Maintenance Manual. [BSC- CG, HCD 1 & DWR] An operation and maintenance manual for gray water, on-site treated nonpotable water , [DWR] and recycled water supply systems required to have a permit in accordance with Section 1501.3, Section 1505.2, and Section 1506.2 shall be supplied to the building owner by the system designer or installer . The operation and maintenance manual shall include the following:

    (1) Diagram(s) of the entire system and the location of system components.

    (2) Instructions for operating and maintaining the system.

    (3) Instructions on maintaining the required water quality for on-site treated nonpotable water systems.

    (4) Details on startup, shutdown, and deactivating the system for maintenance, repair, or other purposes.

    (5) Applicable testing, inspection, and maintenance frequencies in accordance with Section 1501.5 [DWR] or Section 1505.16 as applicable .

    (6) A method of contacting the installer and/or manufacturer(s).

    (7) Directions to the owner or occupant that the manual shall remain with the building throughout the life cycle of the structure.

Frequently asked questions

Who must obtain the operating permit?

The owner (or authorized representative) must obtain the operating permit; it will only be issued after the AHJ inspects and approves the equipment per § 1013.2.

If my insurer inspects the boiler, do I still need AHJ approval?

Yes — insurer inspections are permitted only if the AHJ approves the company inspector; the inspector must file the prescribed reports with the AHJ and the AHJ retains approval authority.

What if my equipment is hard to open for internal inspection?

Internal inspections are required “where construction and operating conditions permit.” If internal access is not possible, coordinate with the AHJ to document why internal inspection is infeasible; external inspection frequency still applies per the applicable § (see § 1013.4–§ 1013.7).

Can the AHJ require inspections more often than the listed frequencies?

Yes. The AHJ inspects equipment “at such intervals as deemed necessary” and must follow ASHRAE/ACCA 180; the schedules in § 1013.4–§ 1013.7 are minimum frequencies.

Is there any residential exemption to getting an operating permit?

Yes — operation of certain boilers and pressure vessels in residential occupancies of less than six dwelling units and utility occupancies is excepted from the operating‑permit requirement in § 1013.2; check with the AHJ for how this applies locally.

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