What testing, periodic inspection and recordkeeping are required for refrigeration systems?

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

• CMC § 608.7 High relevance — show source text

  608.7 Testing of equipment. Refrigeration equipment and systems having a refrigerant circuit containing more than 220 pounds (100 kg) of Group A1 or 30 pounds (14 kg) of any other group refrigerant shall be subject to periodic testing in accordance with Section 608.7.1. Records of tests shall be maintained. Tests of emergency devices or systems required by this chapter shall be conducted by persons trained and qualified in refrigeration systems.

  6-10 2025 CALIFORNIA FIRE CODE

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

  BUILDING SERVICES AND SYSTEMS

  608.7.1 Periodic testing. The following emergency devices or systems shall be periodically tested in accordance with the manufacturer’s instructions and as required by the fire code official.

  1. Treatment and flaring systems.
  2. Valves and appurtenances necessary to the operation of emergency refrigeration control boxes.
  3. Fans and associated equipment intended to operate emergency ventilation systems.
  4. Detection and alarm systems.

  608.8 Emergency signs. Refrigeration units or systems having a refrigerant circuit containing more than 220 pounds (100 kg) of Group A1 or 30 pounds (14 kg) of any other group refrigerant shall be provided with approved emergency signs, charts and labels in accordance with NFPA 704. Hazard signs shall be in accordance with the California Mechanical Code for the classification of refrigerants listed therein.

  608.9 Refrigerant detection. Machinery rooms shall be provided with a refrigerant detector with an audible and visible alarm. Where ammonia is used as the refrigerant, detection shall comply with IIAR 2. For refrigerants other than ammonia, refrigerant detection shall comply with Section 608.9.1.

  608.9.1 Refrigerants other than ammonia. A detector, or a sampling tube that draws air to a detector, shall be provided at an approved location where refrigerant from a leak is expected to accumulate. The system shall be designed to initiate audible and visible alarms inside of and outside each entrance to the refrigerating machinery room and transmit a signal to an approved location where the concentration of refrigerant detected exceeds the lesser of the following:

  1. The corresponding TLV-TWA values shown in the California Mechanical Code for the refrigerant classification.
  2. Twenty-five percent of the lower flammable limit (LFL).

  Detection of a refrigerant concentration exceeding the upper detection limit or 25 percent of the lower flammable limit (LFL), whichever is lower, shall stop refrigerant equipment in the machinery room in accordance with Section 608.10.1.

  608.10 Remote controls. Where flammable refrigerants are used and compliance with Section 1106 of the California Mechanical Code is required, remote control of the mechanical equipment and appliances located in the machinery room as required by Sections 608.10.1 and 608.10.2 shall be provided at an approved location immediately outside the machinery room and adjacent to its principal entrance.

  608.10.1 Refrigeration system emergency shutoff. A clearly identified switch of the break-glass type or with an approved tamperresistant cover shall provide off-only control of refrigerant compressors, refrigerant pumps and normally closed automatic refrigerant valves located in the machinery room. Additionally, this equipment shall be automatically shut off when the refrigerant vapor concentration in the machinery room exceeds the vapor detector’s upper detection limit or 25 percent of the LEL, whichever is lower.

• CMC § 109.3 High relevance — show source text

  [A] 109.3 Concealed work. It shall be the duty of the permit applicant to cause the work to remain visible and able to be accessed for inspection purposes. Where any installation subject to inspection prior to use is covered or concealed without having first been inspected, the fire code official shall have the authority to require that such work be made visible and able to be accessed for inspection. Neither the fire code official nor the jurisdiction shall be liable for expense entailed in the removal or replacement of any material required to allow inspection.

  [A] 109.4 Approvals. Approval as the 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 provisions of this code or of other ordinances of the jurisdiction shall not be valid.

  SECTION 110—MAINTENANCE

  [A] 110.1 Maintenance of safeguards. Where any device, equipment, system, condition, arrangement, level of protection, or any other feature is required for compliance with the provisions of this code, or otherwise installed, such device, equipment, system, condition, arrangement, level of protection, or other feature shall thereafter be continuously maintained in accordance with this code and applicable referenced standards.

  [A] 110.2 Testing and operation. Equipment requiring periodic testing or operation to ensure maintenance shall be tested or operated as specified in this code.

  [A] 110.2.1 Reinspection and testing. Where any work or installation does not pass an initial test or inspection, the necessary corrections shall be made so as to achieve compliance with this code. The work or installation shall then be resubmitted to the fire code official for inspection and testing.

  [A] 110.3 Recordkeeping. A record of periodic inspections, tests, servicing and other operations and maintenance shall be maintained on the premises or other approved location for not less than 3 years, or a different period of time where specified in this code or referenced standards. Records shall be made available for inspection by the fire code official, and a copy of the records shall be provided to the fire code official on request.

  The fire code official is authorized to prescribe the form and format of such recordkeeping. The fire code official is authorized to require that certain required records be filed with the fire code official.

  [A] 110.4 Supervision. Maintenance and testing shall be under the supervision of a responsible person who shall ensure that such maintenance and testing are conducted at specified intervals in accordance with this code.

  2025 CALIFORNIA FIRE CODE 1-27

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

  DIVISION II—SCOPE AND ADMINISTRATION

  110.5 Rendering equipment inoperable. Portable or fixed fire-extinguishing systems or devices, and fire-warning systems, shall be provided with ready access and shall not be rendered inoperative, except as necessary during emergencies, maintenance, repairs, alterations, drills or prescribed testing.

  [A] 110.6 Overcrowding. Overcrowding or admittance of any person beyond the approved capacity of a building or a portion thereof shall not be allowed. The fire code official, on finding any overcrowding conditions or obstructions in aisles, passageways or other means of egress, or on finding any condition that constitutes a life safety hazard, shall be authorized to cause the event to be stopped until such condition or obstruction is corrected.

  SECTION 111—SERVICE UTILITIES

• CMC § 608.1 High relevance — show source text

  SECTION 608—MECHANICAL REFRIGERATION

  [M] 608.1 Scope. Refrigeration systems shall be installed in accordance with the California Mechanical Code .

  608.1.1 Refrigerants other than ammonia. Where a refrigerant other than ammonia is used, refrigeration systems and the buildings in which such systems are installed shall be in accordance with ASHRAE 15.

  608.1.2 Ammonia refrigeration. Refrigeration systems using ammonia refrigerant and the buildings in which such systems are installed shall comply with IIAR 2 for system design; IIAR 6 for inspection, testing and maintenance; and IIAR 7 for operating procedures. Decommissioning of ammonia refrigeration systems shall comply with IIAR 8, and engineering practices for existing ammonia refrigeration systems shall be in accordance with IIAR 9.

  608.2 Permits. An operational permit shall be obtained for refrigeration systems as set forth in Section 105.5.46.

  [M] 608.3 Refrigerants. The use and purity of new, recovered and reclaimed refrigerants shall be in accordance with the California Mechanical Code .

  [M] 608.4 Refrigerant classification. Refrigerants shall be classified in accordance with the California Mechanical Code .

  [M] 608.5 Change in refrigerant type. A change in the type of refrigerant in a refrigeration system shall be in accordance with the California Mechanical Code .

  608.6 Access. Access to refrigeration systems having a refrigerant circuit containing more than 220 pounds (100 kg) of Group A1 or 30 pounds (14 kg) of any other group refrigerant shall be provided for the fire department at all times as required by the fire code official.

  608.7 Testing of equipment. Refrigeration equipment and systems having a refrigerant circuit containing more than 220 pounds (100 kg) of Group A1 or 30 pounds (14 kg) of any other group refrigerant shall be subject to periodic testing in accordance with Section 608.7.1. Records of tests shall be maintained. Tests of emergency devices or systems required by this chapter shall be conducted by persons trained and qualified in refrigeration systems.

  6-10 2025 CALIFORNIA FIRE CODE

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

  BUILDING SERVICES AND SYSTEMS

  608.7.1 Periodic testing. The following emergency devices or systems shall be periodically tested in accordance with the manufacturer’s instructions and as required by the fire code official.

  1. Treatment and flaring systems.
  2. Valves and appurtenances necessary to the operation of emergency refrigeration control boxes.
  3. Fans and associated equipment intended to operate emergency ventilation systems.
  4. Detection and alarm systems.

  608.8 Emergency signs. Refrigeration units or systems having a refrigerant circuit containing more than 220 pounds (100 kg) of Group A1 or 30 pounds (14 kg) of any other group refrigerant shall be provided with approved emergency signs, charts and labels in accordance with NFPA 704. Hazard signs shall be in accordance with the California Mechanical Code for the classification of refrigerants listed therein.

  608.9 Refrigerant detection. Machinery rooms shall be provided with a refrigerant detector with an audible and visible alarm. Where ammonia is used as the refrigerant, detection shall comply with IIAR 2. For refrigerants other than ammonia, refrigerant detection shall comply with Section 608.9.1.

• CMC § 3.3.35 High relevance — show source text

  Liquid-Tight. Constructed and performing in a way that prevents the passage of liquid at any temperature. [NFPA 96:3.3.35]

  Listed (Third Party Certified). Equipment or materials included in a list published by a listing agency (accredited conformity assessment body) that maintains periodic inspection of current production of listed equipment or materials and whose listing states either that the equipment or material complies with approved standards or has been tested and found suitable for use in a specified manner. [HCD 1 & HCD 2] “Listed” means all products that appear in a list published by an approved testing or listing agency. For additional infor- mation, see Health and Safety Code Section 17920(h).

  Listed and Listing. [SFM] “Listed” and “Listing” are terms referring to equipment or materials included in a list published by an approved testing laboratory, inspection agency, or other organization concerned with product evalu- ation that maintains periodic inspection of current produc- tions of listed equipment or materials and which listing states that the material or equipment complies with approved nationally recognized codes, standards, or tests and has been tested or evaluated and found suitable for use in a specific manner. These terms shall also mean equipment or materials accepted by the State Fire Marshal as conforming to the pro- visions of these regulations and which are included in a list published by the State Fire Marshal.

  Listing Agency. An agency accredited by an independent and authoritative conformity assessment body to operate a material and product listing and labeling (certification) system and that are accepted by the Authority Having Jurisdiction, which is in the business of listing or labeling. The system includes initial and ongoing product testing, a periodic inspection on current production of listed (certified) products, and that makes available a published report of such listing in which specific information is included that the material or product is in accordance with applicable standards and found safe for use in a specific manner. [HCD 1 & HCD 2] “List- ing Agency” means an agency approved by the Department that is in the business of listing and labeling products, materials, equipment, and installations tested by an approved testing agency, and that maintains a periodic inspection program on current production of listed products, equipment, and installa- tions, and that at least annually makes available a published report of these listings. For additional information, see Health and Safety Code Section 17920(i).

  Low-Probability Pump. A pump that (a) is permanently sealed to prevent atmospheric release of the pumped fluid, (b) incorporates a static seal to prevent atmospheric release of the pumped fluid, or (c) incorporates not less than two sequential dynamic shaft seals and automatically shuts down

  upon failure of any seal to prevent atmospheric release of the pumped fluid. [ASHRAE 15:3]

  Lowside. Refers to the parts of a refrigeration system subjected to approximate evaporator pressure.

  215.0 – M –

  Machinery. The refrigeration equipment forming a part of the refrigeration system, including, but not limited to, the following: compressors, condensers, liquid receivers, evaporators, and connecting piping.

• CMC § 215.0 High relevance — show source text

  ** An agency accredited by an independent and authoritative conformity assessment body to operate a material and product listing and labeling (certification) system and that are accepted by the Authority Having Jurisdiction, which is in the business of listing or labeling. The system includes initial and ongoing product testing, a periodic inspection on current production of listed (certified) products, and that makes available a published report of such listing in which specific information is included that the material or product is in accordance with applicable standards and found safe for use in a specific manner. [HCD 1 & HCD 2] “List- ing Agency” means an agency approved by the Department that is in the business of listing and labeling products, materials, equipment, and installations tested by an approved testing agency, and that maintains a periodic inspection program on current production of listed products, equipment, and installa- tions, and that at least annually makes available a published report of these listings. For additional information, see Health and Safety Code Section 17920(i).

  Low-Probability Pump. A pump that (a) is permanently sealed to prevent atmospheric release of the pumped fluid, (b) incorporates a static seal to prevent atmospheric release of the pumped fluid, or (c) incorporates not less than two sequential dynamic shaft seals and automatically shuts down

  upon failure of any seal to prevent atmospheric release of the pumped fluid. [ASHRAE 15:3]

  Lowside. Refers to the parts of a refrigeration system subjected to approximate evaporator pressure.

  215.0 – M –

  Machinery. The refrigeration equipment forming a part of the refrigeration system, including, but not limited to, the following: compressors, condensers, liquid receivers, evaporators, and connecting piping.

  Machinery Room. [SFM] Machinery Room is a room in which a refrigeration system is permanently installed and operated but not including evaporators located in a cold stor- age room, refrigerator box, air-cooled space or other enclosed space. Closets solely contained within, and opening only into, a room shall not be considered machinery rooms, but shall be considered a part of the machinery rooms in which they are contained or open into. It is not the intent of this definition to cause the space in which unit or self-con- tained systems of Group I refrigerants are locate to be clas- sified as machinery rooms.

  Mechanical System. A set of components, devices, appliances, and equipment intended to perform a function(s) for which the system is designed, as regulated by this code.

  Mechanical Ventilation. Ventilation provided by mechanically powered equipment, such as motor-driven fans and blowers, but not by devices such as wind-driven turbine ventilators and mechanically operated windows. [ASHRAE 62.1:3]

  Mid-Story Guide. A support designed to keep piping in alignment, located mid-way between floors or a floor and ceiling.

  216.0 – N –

  Natural Ventilation. Ventilation provided by thermal, wind, or diffusion effects through doors, windows, or other intentional openings in the building. [ASHRAE 62.1:3]

  Noncombustible Material. As applied to building construction material, means a material that in the form in which it is used is either one of the following:

• CMC § 1108.2 Medium relevance — show source text

  1108.2 Electrical . . . . . . . . . . . . . . . . . . . . 237

  1108.3 Emergency Shutoff . . . . . . . . . . . . 237

  2025 CALIFORNIA MECHANICAL CODE

  1108.4 Installation, Maintenance, and Testing . . . . . . . . . . . . . . . . . . . . . 237

  1108.5 Emergency Pressure Control System . . . . . . . . . . . . . . . . . . . . . 237

  1109.0 Refrigeration Piping, Containers, and Valves . . . . . . . . . . . . . . . . . . 237

  1109.1 Materials . . . . . . . . . . . . . . . . . . . . 237

  Table 1109.1 Materials for Refrigerant Piping, Tubing, and Fittings . . . . . . . . . . . 239

  1109.2 Joints . . . . . . . . . . . . . . . . . . . . . . 239

  1109.3 Penetration of Piping . . . . . . . . . . 239

  1109.4 Location of Refrigeration Piping . . 239

  1109.5 Underground Piping . . . . . . . . . . . 239

  1109.6 Support . . . . . . . . . . . . . . . . . . . . . 239

  1109.7 Pipe Enclosure . . . . . . . . . . . . . . . 239

  1109.8 Visual Inspection . . . . . . . . . . . . . 240

  1109.9 Condensation . . . . . . . . . . . . . . . . 240

  1109.10 Identification . . . . . . . . . . . . . . . . . 240

  1110.0 Valves. . . . . . . . . . . . . . . . . . . . . . 240

  1110.1 More than 6.6 Pounds of

  Refrigerant . . . . . . . . . . . . . . . . . . 240

  1110.2 More than 110 Pounds of

  Refrigerant . . . . . . . . . . . . . . . . . . 240

  1110.3 Support . . . . . . . . . . . . . . . . . . . . . 240

  1110.4 Access . . . . . . . . . . . . . . . . . . . . . 240

  1110.5 Identification . . . . . . . . . . . . . . . . . 240

  1111.0 Pressure-Limiting Devices . . . . . . 240

  1111.1 Where Required . . . . . . . . . . . . . . 240

  1111.2 Setting . . . . . . . . . . . . . . . . . . . . . 240

  1111.3 Location . . . . . . . . . . . . . . . . . . . . 240

  1111.4 Emergency Stop . . . . . . . . . . . . . . 240

  1112.0 Pressure-Relief Devices . . . . . . . . 241

• CMC § 1106.3 Medium relevance — show source text

  1106.3 Normal Operation . . . . . . . . . . . . . 233

  1106.4 Natural Ventilation . . . . . . . . . . . . 234

  1106.5 Combustion Air . . . . . . . . . . . . . . . 234

  1106.6 Ventilation Intake . . . . . . . . . . . . . 234

  1106.7 Maximum Temperature . . . . . . . . 234

  1106.8 Refrigerant Parts in Air Duct. . . . . 234

  1106.9 Dimensions. . . . . . . . . . . . . . . . . . 234

  1106.10 Exits . . . . . . . . . . . . . . . . . . . . . . . 234

  1106.11 Machinery Room, A2L and B2L . . 234

  Table 1106.11.10.2 Refrigerant Detector Set Points, Response Times, Alarms, and Ventilation Levels . . . . . . . . . . . . . 235

  Table 1106.11.11.2 Level 1 Ventilation Rate for

  Class 2L Refrigerants . . . . . . . . . . . 236

  1107.0 Machinery Room, Special Requirements . . . . . . . . . . . . . . . . 236

  1107.1 General. . . . . . . . . . . . . . . . . . . . . 236

  1108.0 Refrigeration Machinery Room Equipment and Controls . . . . . . . . 237

  1108.1 General. . . . . . . . . . . . . . . . . . . . . 237

  1108.2 Electrical . . . . . . . . . . . . . . . . . . . . 237

  1108.3 Emergency Shutoff . . . . . . . . . . . . 237

  2025 CALIFORNIA MECHANICAL CODE

  1108.4 Installation, Maintenance, and Testing . . . . . . . . . . . . . . . . . . . . . 237

  1108.5 Emergency Pressure Control System . . . . . . . . . . . . . . . . . . . . . 237

  1109.0 Refrigeration Piping, Containers, and Valves . . . . . . . . . . . . . . . . . . 237

  1109.1 Materials . . . . . . . . . . . . . . . . . . . . 237

  Table 1109.1 Materials for Refrigerant Piping, Tubing, and Fittings . . . . . . . . . . . 239

  1109.2 Joints . . . . . . . . . . . . . . . . . . . . . . 239

  1109.3 Penetration of Piping . . . . . . . . . . 239

  1109.4 Location of Refrigeration Piping . . 239

  1109.5 Underground Piping . . . . . . . . . . . 239

  1109.6 Support . . . . . . . . . . . . . . . . . . . . . 239

  1109.7 Pipe Enclosure . . . . . . . . . . . . . . . 239

  1109.8 Visual Inspection . . . . . . . . . . . . . 240

• CMC § 110.3 Medium relevance — show source text

  [A] 110.3 Recordkeeping. A record of periodic inspections, tests, servicing and other operations and maintenance shall be maintained on the premises or other approved location for not less than 3 years, or a different period of time where specified in this code or referenced standards. Records shall be made available for inspection by the fire code official, and a copy of the records shall be provided to the fire code official on request.

  The fire code official is authorized to prescribe the form and format of such recordkeeping. The fire code official is authorized to require that certain required records be filed with the fire code official.

  [A] 110.4 Supervision. Maintenance and testing shall be under the supervision of a responsible person who shall ensure that such maintenance and testing are conducted at specified intervals in accordance with this code.

  2025 CALIFORNIA FIRE CODE 1-27

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

  DIVISION II—SCOPE AND ADMINISTRATION

  110.5 Rendering equipment inoperable. Portable or fixed fire-extinguishing systems or devices, and fire-warning systems, shall be provided with ready access and shall not be rendered inoperative, except as necessary during emergencies, maintenance, repairs, alterations, drills or prescribed testing.

  [A] 110.6 Overcrowding. Overcrowding or admittance of any person beyond the approved capacity of a building or a portion thereof shall not be allowed. The fire code official, on finding any overcrowding conditions or obstructions in aisles, passageways or other means of egress, or on finding any condition that constitutes a life safety hazard, shall be authorized to cause the event to be stopped until such condition or obstruction is corrected.

  SECTION 111—SERVICE UTILITIES

  [A] 111.1 Authority to disconnect service utilities. The fire code official shall have the authority to authorize disconnection of utility service to the building, structure or system in order to safely execute emergency operations or to eliminate an immediate hazard. The fire code official shall notify the serving utility and, where possible, the owner or the owner’s authorized agent and the occupant of the building, structure or service system of the decision to disconnect prior to taking such action. If not notified prior to disconnection, then the owner, the owner’s authorized agent or occupant of the building, structure or service system shall be notified in writing as soon as practical thereafter.

  SECTION 112—MEANS OF APPEALS

  [A] 112.1 General. In order to hear and decide appeals of orders, decisions or determinations made by the fire code official relative to the application and interpretation of this code, there shall be and is hereby created a board of appeals. The board of appeals shall be appointed by the applicable governing authority and shall hold office at its pleasure. The board shall adopt rules of procedure for conducting its business and shall render all decisions and findings in writing to the appellant with a duplicate copy to the fire code official.

  [A] 112.2 Limitations on authority. An application for appeal shall be based on a claim that the true intent of this code or the rules legally adopted thereunder have been incorrectly interpreted, the provisions of this code do not fully apply or an equivalent or better form of construction is proposed. The board shall not have authority to waive requirements of this code.

  [A] 112.3 Qualifications. The board of appeals shall consist of members who are qualified by experience and training on matters pertaining to the provisions of this code and are not employees of the jurisdiction.

• CMC § 6.1507 Medium relevance — show source text

  LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
  2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
  Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
  where× = Condenser DT + LIFT
  COPadj = Kadj * COPstd|1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
  2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
  Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
  where× = Condenser DT + LIFT
  COPadj = Kadj * COPstd|1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
  2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
  Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
  where× = Condenser DT + LIFT
  COPadj = Kadj * COPstd|1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
  2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
  Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
  where× = Condenser DT + LIFT
  COPadj = Kadj * COPstd|1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
  2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
  Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
  where× = Condenser DT + LIFT
  COPadj = Kadj * COPstd|1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
  2. Condenser DT = Leaving Condenser Water Temperature (°F) – Entering Condenser Water Temperature (°F)
  Kadj = 6.1507 – 0.30244(×) + 0.0062692(×)2 – 0.000045595(×)3
  where× = Condenser DT + LIFT
  COPadj = Kadj * COPstd|

  A6.207.1.2 Controls for heat pumps with supplementary electric resistance heaters. Heat pumps with supplementary electric resistance heaters shall have controls:

  A6.207.1.2.1 That prevent supplementary heater operation when the heating load can be met by the heat pump alone; and

• CMC § 8.13.6.2 Medium relevance — show source text

  (1) Refrigerant compressors

  (2) Refrigerant pumps

  (3) Normally closed automatic refrigerant valves

  (4) Other unclassified electrical sources of ignition with apparent power rating greater than 1 kVA, where the apparent power is the product of the circuit voltage and current rating. [ASHRAE 15:8.13.6.2] 1106.11.7 Mechanical Equipment Control. Remote control of the mechanical equipment in the refrigerating machinery room shall be provided immediately outside the machinery room door solely for the purpose of shutting down the equipment in an emergency. Ventilation fans shall be on a separate electrical circuit and have a control switch located immediately outside the machinery room door. [ASHRAE 15:8.13.7] 1106.11.8 Refrigerant Detectors. Each refrigerating machinery room in accordance with Section 1106.11 shall contain one or more refrigerant detectors in accordance with Section 1106.11.9. The detector(s) sensing element shall be located in areas where refrigerant from a leak will concentrate, with one or more set points that activate responses in accordance with Section 1106.11.10 for alarms and Section 1106.11.11 for mechanical ventilation. Multiport-type devices shall be prohibited. {ASHRAE 15:8.13.8} 1106.11.9 Refrigerant Detectors Requirements. Refrigerant detectors required by Section 1106.11 shall meet all of the following conditions:

  (1) A refrigerant detector shall be capable of detecting each of the specific refrigerant designations in the machinery room.

  (2) The refrigerant detector shall activate responses within a time not to exceed a limit specified in Section 1106.11.10 and Section 1106.11.11 after exposure to refrigerant concentration exceeding a limit value specified in Section 1106.11.10 and Section 1106.11.11.

  (3) The refrigerant detector shall have a set point not greater than the applicable Occupational Exposure Limit (OEL) value in accordance with Table 1102.3. The applicable OEL value shall be the lowest OEL value for any refrigerant designation in the machinery room. For refrigerants that do not have an OEL value in Table 1102.3, use a value determined in accordance with the OEL as defined by ASHRAE 34 where approved by the Authority Having Jurisdiction.

  (4) The refrigerant detector shall have a set point not more than the applicable Refrigerant Concentration Limit (RCL) value in accordance with Table 1102.3. The applicable RCL value shall be the lowest RCL value for any refrigerant designation in the machinery room. For refrigerants that do not have a RCL value in Table 1102.3, use a value determined in accordance with the RCL as defined by ASHRAE 34 where approved by the Authority Having Jurisdiction.

  (5) The refrigerant detector shall provide a means for automatic self-testing and shall be in accordance with Section 1106.11.10.4. The refrigerant detector shall be tested during installation and annually thereafter in accordance with the fire code, or at an interval not exceeding the manufacturer’s installation instructions, whichever is less. Testing shall verify compliance with the alarm set points and response times per Section 1106.11.10 and Section 1106.11.11. [ASHRAE 15:8.13.9]

• CMC § 1220.4.2 Medium relevance — show source text

  8|1220.4.2 – 1220.4.6| |1221.7|1221.6| |1308.2 – 1308.4.1|1308.3 – 1308.5.1| |Table 1308.3.1|Table 1308.4.1| |1308.4.2|1308.5.2| |1308.4.2.2 – 1308.6.4|1308.5.2.1 – 1308.7.3| |Table 1308.4.6.2|Table 1308.5.6.2| |1308.6.5 – 1308.13.1|1308.7.7 – 1308.14.1| |1312.1.2 – 1312.1.3|1312.1.1 – 1312.1.2| |Chapter 17|Appendix F| |Chapter 18|Chapter 17| |D 103.2|D 103.1| |E 503.5.6.7|E 503.5.6.6| |E 503.5.7.2 – E 503.5.7.6|E 503.5.7.1 – E 503.5.7.5| |Table E 503.5.7.2|Table E 503.5.7.1| |Table E 503.5.7.6|Table E 503.5.7.5| |Table E 503.5.10.1.2(1)|Table E 503.5.10(1)| |Table E 503.5.10.1.2(2)|Table E 503.5.10(2)| |E 503.5.10.1.2|E 503.5.10| |E 503.5.10.2 – E 503.5.10.2.2|E 503.5.10.1 – E 503.5.10.1.2| |E 503.5.12.1|E 503.5.12| |E 503.5.12.2|E 503.5.12.1| |E 503.6.5.4|E 503.6.5.4.1|

  xxii 2025 CALIFORNIA MECHANICAL CODE

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• CMC § 910.4.3.1 Medium relevance — show source text

  910.4.3.1 Makeup air. Makeup air openings shall be provided within 6 feet (1829 mm) of the floor level. Operation of makeup air openings shall be manual or automatic. The minimum gross area of makeup air inlets shall be 8 square feet per 1,000 cubic feet per minute (0.74 m [2] per 0.4719 m [3] /s) of smoke exhaust.

  910.4.4 Activation. The mechanical smoke removal system shall be activated by manual controls only.

  910.4.5 Manual control location. Manual controls shall be located where they are able to be accessed by the fire service from an exterior door of the building and separated from the remainder of the building by not less than 1-hour fire barriers constructed in accordance with Section 707 of the California Building Code or horizontal assemblies constructed in accordance with Section 711 of the California Building Code, or both.

  910.4.6 Control wiring. Wiring for operation and control of mechanical smoke removal systems shall be connected ahead of the main disconnect in accordance with Section 701.12E of the California Electrical Code and be protected against interior fire exposure to temperatures in excess of 1,000°F (538°C) for a period of not less than 15 minutes.

  910.4.7 Controls. Where building air-handling and mechanical smoke removal systems are combined or where independent building air-handling systems are provided, fans shall automatically shut down in accordance with the California Mechanical Code . The manual controls provided for the smoke removal system shall have the capability to override the automatic shutdown of fans that are part of the smoke removal system.

  910.5 Maintenance and testing. Maintenance and testing of smoke and heat vents and mechanical smoke removal systems shall be in accordance with Sections 910.5.1 and 910.5.2. A written record of inspection, testing and maintenance that includes the date, identification of personnel involved, any unsatisfactory result, corrective action taken and replaced parts shall be maintained on the premises.

  910.5.1 Smoke and heat vents. Smoke and heat vents shall be maintained in an operative condition. Inspection, testing and maintenance shall be in accordance with NFPA 204 except as follows:

  1. Mechanically operated smoke and heat vents shall be inspected annually and operationally tested not less than every 5

  years. 2. Gravity dropout smoke and heat vents shall be inspected annually. 3. Fused, damaged or painted fusible links shall be replaced.

  910.5.2 Mechanical smoke removal systems. Mechanical smoke removal systems shall be maintained in accordance with NFPA 204 and the equipment manufacturer’s instructions except as follows:

  1. Systems shall be inspected and operationally tested annually.
  2. Testing shall include the operation of all system components, controls and ancillary equipment, such as makeup air openings.
  3. A written schedule for routine maintenance and operational testing shall be established and testing shall be conducted in accordance with the schedule.

  SECTION 911—EXPLOSION CONTROL

  911.1 General. Explosion control shall be provided in the following locations:

  1. Where a structure, room or space is occupied for purposes involving explosion hazards as identified in Table 911.1.
  2. Where quantities of hazardous materials specified in Table 911.1 exceed the maximum allowable quantities in Table 5003.1.1(1).
• CMC § 1105.4 Medium relevance — show source text

  Illumination and

  service receptacles . . . . . . . . . . . . . . . . . . . . . 1105.4

  Location of . . . . . . . . . . . . . . . . . . . . . . . 1104.2, 1105.0

  Refrigeration recovery . . . . . . . . . . . . . . . . . . . . . 1101.2 Supports and anchorage. . . . . . . . . . . . . . . . . . . 1105.2

  Testing of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1116.0 Valves. . . . . . . . . (see Valves, for refrigeration systems)

  REFRIGERATION

  MACHINERY ROOMS

  A2L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1106.11

  B2L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1106.11

  Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220.0

  General . . . . . . . . . . . . . . . . . . . . . . . . . . 1106.0, 1106.2

  REFRIGERATION SPACES

  Concentration limit. . . . . . . 1102.3, 1104.2, Table 1102.3

  Industrial occupancies. . . . . . . . . . . . . . . . . . . . . 1104.4

  Institutional occupancies . . . . . . . . . . . . . . . . . . . 1104.3

  Nonconnecting spaces . . . . . . . . . . . . . . . . . . . 1104.2.2

  Refrigerated spaces . . . . . . . . . . . . . . . . . . . . . . 1104.4

  Ventilated spaces . . . . . . . . . . . . . . . . . . . . . . . 1104.2.3

  Volume calculation . . . . . . . . . . . . . . . . . . . . . . 1104.2.1

  REFRIGERATION SYSTEM CLASSIFICATION

  Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220.0

  High-probability systems. . . . . . . . . . . . . . . . . . 1103.2.1

  Higher flammability refrigerants. . . . . . . . . . . . . . 1103.3

  Low-probability . . . . . . . . . . . . . . . . . . . . . . . . . 1103.2.2

  REFRIGERATION SYSTEMS

  Absorption . . . . . . . . . . . . . . . . . . . . . . . . . 220.0, 307.4

• CMC § 120.6 Medium relevance — show source text

  water static pressure|45|AHRI 420| |Direct Expansion, Halocarbon
  Refrigerant, Cooler/Dock|Dry Coil
  +25°F saturated evaporating dew point temperature
  +35°F entering drybulb temperature
  0 in. water static pressure|45|AHRI 1250| |Direct Expansion, Halocarbon
  Refrigerant, Freezer|Dry Coil
  -20°F saturated evaporating dew point temperature
  -10°F entering drybulb temperature
  0 in. water static pressure|40|AHRI 1250| |1. Direct expansion: Evaporator in which leaving refrigerant vapor is superheated.
  2. Liquid overfeed: Evaporator in which refrigerant liquid is supplied at a recirculation rate greater than 1.
  3. Applicable test procedure and reference year are provided under the definitions.|1. Direct expansion: Evaporator in which leaving refrigerant vapor is superheated.
  2. Liquid overfeed: Evaporator in which refrigerant liquid is supplied at a recirculation rate greater than 1.
  3. Applicable test procedure and reference year are provided under the definitions.|1. Direct expansion: Evaporator in which leaving refrigerant vapor is superheated.
  2. Liquid overfeed: Evaporator in which refrigerant liquid is supplied at a recirculation rate greater than 1.
  3. Applicable test procedure and reference year are provided under the definitions.|1. Direct expansion: Evaporator in which leaving refrigerant vapor is superheated.
  2. Liquid overfeed: Evaporator in which refrigerant liquid is supplied at a recirculation rate greater than 1.
  3. Applicable test procedure and reference year are provided under the definitions.|

  4. Condensers. New fan-powered condensers on new refrigeration systems shall conform to the following: A. Design saturated condensing temperatures for evaporative-cooled condensers and water-cooled condensers served by fluid coolers or cooling towers shall be less than or equal to: i. The design wetbulb temperature plus 20°F in locations where the design wetbulb temperature is less than or equal to 76°F; or ii. The design wetbulb temperature plus 19°F in locations where the design wetbulb temperature is between 76°F and 78°F; or

  2025 CALIFORNIA ENERGY CODE 81

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

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

  iii. The design wetbulb temperature plus 18°F in locations were the design wetbulb temperature is greater than or equal to 78°F. Exception 1 to Section 120.6(a)4A: Compressors and condensers on a refrigeration system for which more than 20 percent of the total design refrigeration cooling load is for quick chilling/freezing of products (space with design cooling capacities of greater than 240 Btu/hr-ft [2] ), or process refrigeration cooling for other than a refrigerated space. Exception 2 to Section 120.6(a)4A: Condensing units that are components of walk-in coolers or walk-in freezers within the scope of the Appliance Efficiency Regulations. B. Design saturated condensing temperatures for air-cooled condensers shall be less than or equal to: i. The design drybulb temperature plus 10°F for systems serving freezers; ii.

• CMC § 220.0 Medium relevance — show source text

  Recycled . . . . . . . . . . . . . . . . . . . . . . . . 220.0, 1104.8.2 Refrigerant designation, definition . . . . . . . . . . . . 220.0 Requirements for . . . . . . . . . . . . . . . . . . . . . . . . . 1104.0 Safety classification, definition . . . . . . . . . . . . . . . 220.0

  Storage of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1105.12

  Types used . . . . . . . . . . . . 1102.3, 1104.8, Table 1102.3

  Zeotropic, definition. . . . . . . . . . . . . . . . . . . . . . . . 228.0

  REFRIGERATION EQUIPMENT

  Access. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1105.3

  Coils . . . . . . . . . . . . . . . . . 310.6, 903.2.6, 904.8, 905.7

  Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1108.0

  Identification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1115.0

  Illumination and

  service receptacles . . . . . . . . . . . . . . . . . . . . . 1105.4

  Location of . . . . . . . . . . . . . . . . . . . . . . . 1104.2, 1105.0

  Refrigeration recovery . . . . . . . . . . . . . . . . . . . . . 1101.2 Supports and anchorage. . . . . . . . . . . . . . . . . . . 1105.2

  Testing of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1116.0 Valves. . . . . . . . . (see Valves, for refrigeration systems)

  REFRIGERATION

  MACHINERY ROOMS

  A2L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1106.11

  B2L. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1106.11

  Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220.0

  General . . . . . . . . . . . . . . . . . . . . . . . . . . 1106.0, 1106.2

  REFRIGERATION SPACES

• CMC § 302.3.4 Medium relevance — show source text

  Design approval. . . . . . . . . . . . . . . . . . . . . . . . . 302.3.4

  Design document. . . . . . . . . . . . . . . . . . . . . . . . 302.3.3

  Design review . . . . . . . . . . . . . . . . . . . . . . . . . . 302.3.5

  Inspection and testing . . . . . . . . . . . . . . . . . . . . 302.3.6

  Permit application . . . . . . . . . . . . . . . . . . . . . . . 302.3.1

  Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . 302.3.2

  AMMONIA . . . . . . . . . . . . . . . . . . . . 1102.1, 1102.2, 1102.3,

  Table 1102.3, 1104.4,

  1106.2, 1302.3

  ANCHORAGE OF

  Appliances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303.4

  Boilers and pressure vessels . . . . . . . . . . . . . . . . 1001.5

  Cooling towers. . . . . . . . . . . . . . . . . . . . . . . . . . . 1120.0

  Evaporative condensers . . . . . . . . . . . . . . . . . . . 1120.0

  Floor furnace seepage pans . . . . . . . . . . . . . . . . 906.10

  Fluid coolers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1120.0

  Fuel gas piping. . . . . . . . . . . . . . . . . . . . . . . . . 1310.3.5

  Radiant panels. . . . . . . . . . . . . . . . . . . . . . . . . 1217.11.2

  Refrigeration equipment

  and piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1105.2

  ANODELESS RISER

  Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.0

  Factory assembled. . . . . . . . . . . . . . . . . . . 1308.4.4.2.1

  Field assembled. . . . . . . . . . . . . . . . . . . . . 1308.4.4.2.2

  APPEALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107.0

  APPLIANCE FLUE OUTLET

  Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.0

• CMC § 805.13.1 Medium relevance — show source text

  An FDD system that does not pass this test shall be permitted to be installed, but no compliance credit will be given. E 805.13.1 Test Procedure. The procedure for performing a functional test for automatic fault detection diagnostics (FDD) for air handling units and zone terminal units shall be in accordance with Section E 805.13.1.1.

  E 805.13.1.1 Functional Testing. The functional testing shall be in accordance with Section E 805.13.1.1.1 and Section E 805.13.1.1.2.

  E 805.13.1.1.1 Functional Testing for Air Handling Units. The functional testing of AHU with FDD controls shall be in accordance with the following steps:

  Step 1: Sensor drift/failure:

  (1) Disconnect outside air temperature sensor from unit controller.

  (2) Verify that the FDD system reports a fault.

  (3) Connect OAT sensor to the unit controller.

  (4) Verify that FDD indicates normal system operation.

  Step 2: Damper/actuator fault:

  (1) From the control system workstation, command the mixing box dampers to full open (100 percent outdoor air).

  (2) Disconnect power to the actuator and verify that a fault is reported at the control workstation.

  (3) Reconnect power to the actuator and command the mixing box dampers to full open.

  (4) Verify that the control system does not report a fault.

  (5) From the control system workstation, command the mixing box dampers to a fullclosed position (0 percent outdoor air).

  (6) Disconnect power to the actuator and verify that a fault is reported at the control workstation.

  (7) Reconnect power to the actuator and command the dampers closed.

  (8) Verify that the control system does not report a fault during normal operation.

  Step 3: Valve/actuator fault:

  (1) From the control system workstation, command the heating and cooling coil valves to full open or closed, then disconnect power to the actuator and verify that a fault is reported at the control workstation.

  Step 4: Inappropriate simultaneous heating, mechanical cooling, and economizing or all functions:

  (1) From the control system workstation, override the heating coil valve and verify that a fault is reported at the control workstation.

  (2) From the control system workstation, override the cooling coil valve and verify that a fault is reported at the control workstation.

  (3) From the control system workstation, override the mixing box dampers and verify that a fault is reported at the control workstation.

  E 805.13.1.1.2 Functional Testing for Zone Terminal Units. The functional testing of one of each type of terminal unit (VAV box) in the project not less than 5 percent of the terminal boxes shall be in accordance with the following steps:

  Step 1: Sensor drift/failure:

  (1) Disconnect the tubing to the differential pressure sensor of the VAV box.

  (2) Verify that control system detects and reports the fault.

  (3) Reconnect the sensor and verify proper sensor operation.

  (4) Verify that the control system does not report a fault.

  Step 2: Damper/actuator fault:

  (1) Damper stuck open.

  (a) Command the damper to full open (room temperature above setpoint).

  (b) Disconnect the actuator to the damper.

  2025 CALIFORNIA MECHANICAL CODE 489

• CMC § 522 Medium relevance — show source text

  522 2025 CALIFORNIA MECHANICAL CODE

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

  APPENDIX E

  CERTIFICATE OF ACCEPTANCE MECH-13A	Col2
  Automatic Fault Detection and Diagnostics (FDD) for Packaged Direct-Expansion Units and Zone (Page 2 of 4) Terminal Units Acceptance	Automatic Fault Detection and Diagnostics (FDD) for Packaged Direct-Expansion Units and Zone (Page 2 of 4) Terminal Units Acceptance
  Project Name/Address:	Project Name/Address:
  System Name or Identification/Tag:	System Location or Area Served:

  Intent: Verify that the system detects common faults in air handling units and zone terminal units.

  Construction Inspection

  1. Instrumentation to perform test includes, but not limited to: a. No instrumentation is required – changes are implemented at the building automation system control station.
  2. Installation.

  a. The functional testing verifies proper installation of the controls for FDD for air handling units and zone terminal units. No additional installation checks are required.

  A. Eligibility Criteria Results.	Results
  Testing of each AHU with FDD controls shall include the following tests:	Testing of each AHU with FDD controls shall include the following tests:
  Step 1: Sensor Drift/Failure:	Step 1: Sensor Drift/Failure:
  a. Disconnect outside air temperature sensor from unit controller.	Y / N
  b. Verify that the FDD system reports a fault.	Y / N
  c. Connect OAT sensor to the unit controller.	Y / N
  d. Verify that FDD indicates normal system operation.	Y / N
  Step 2: Damper/actuator fault.	Step 2: Damper/actuator fault.
  a. From the control system workstation, command the mixing box dampers to full open (100% outdoor air).	Y / N
  b. Disconnect power to the actuator and verify that a fault is reported at the control workstation.	Y / N
  c. Reconnect power to the actuator and command the mixing box dampers to full open.	Y / N
  d. Verify that the control system does not report a fault.	Y / N
  e. From the control system workstation, command the mixing box dampers to a full-closed position (0% outdoor air).	Y / N
  f. Disconnect power to the actuator and verify that a fault is reported at the control workstation.	Y / N
  g. Reconnect power to the actuator and command the dampers closed.

• CMC § 180.2 Medium relevance — show source text

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

  I. Outdoors; or

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

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

  (d) Mechanical acceptance testing.

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

  220 2025 CALIFORNIA ENERGY CODE

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  MULTIFAMILY BUILDINGS—MANDATORY REQUIREMENTS

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

• CMC § 141.0 Medium relevance — show source text

  Exception 1 to Section 141.0(b)2Dii: When it is not possible to achieve the duct leakage criteria in Section 141.0(b)2Dii, then all accessible leaks shall be sealed and verified through a visual inspection and a smoke test performed by a certified mechanical acceptance test technician utilizing the methods specified in Reference Nonresidential Appendix NA7.5.3. Exception 2 to Section 141.0(b)2Dii: Duct sealing. Existing duct systems that are extended, which are constructed insulated or sealed with asbestos are not required to comply with Subsection 141.0(b)2Dii. iii. If new ducts installed as part of an alteration are not required to comply with leakage testing specified by Section 141.0(b)2Di or 141.0(b)2Dii, then the new ducts shall meet the duct leakage testing requirements of CMC Section 603.9.2.

  E. Altered space-conditioning systems. When a space-conditioning system is altered by the installation or replacement of space-conditioning system equipment (including replacement of the air handler, outdoor condensing unit of a split system air conditioner or heat pump, or cooling or heating coil: i. For all altered units where the existing thermostat does not comply with the requirements for demand responsive controls specified in Section 110.12, the existing thermostat shall be replaced with a demand responsive thermostat that complies with Section 110.12. All newly installed space-conditioning systems requiring a thermostat shall be equipped with a demand responsive thermostat that complies with Section 110.12; and ii. The duct system that is connected to the new or replaced space-conditioning system equipment shall be sealed in accordance with Section 141.0(b)2Dii. Exception 1 to Section 141.0(b)2Eii: Duct sealing. Buildings altered so that the duct system no longer meets the criteria of Section 141.0(b)2Dii. Exception 2 to Section 141.0(b)2Eii: Duct sealing. Duct systems that are documented to have been previously sealed as confirmed through field verification and diagnostic testing in accordance with procedures in Reference Nonresidential Appendix NA2. Exception 3 to Section 141.0(b)2Eii: Duct sealing. Existing duct systems constructed, insulated or sealed with asbestos are not required to comply with Subsection 141.0(b)2Eii. F. Spaces with lighting systems installed for the first time shall meet the requirements of Sections 110.9, 130.0, 130.1, 130.2, 130.4, 140.3(c), 140.6 and 140.7. G. When the requirements of Section 130.1(d) are triggered by the addition of skylights to an existing building and the lighting system is not recircuited, the daylighting control need not meet the multilevel requirements in Section 130.1(d). H. New internally and externally illuminated signs shall meet the requirements of Sections 110.9, 130.3 and 140.8. I. Altered indoor lighting systems. Alterations to indoor lighting systems that include 10% or more of the luminaires serving an enclosed space shall meet the requirements of i, ii, or iii below: i. The alteration shall comply with the indoor lighting power requirements specified in Section 140.6 and the lighting control requirements specified in Table 141.0-F; ii.

• CMC § 5.3 Medium relevance — show source text

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

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

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

  SECTION 120.5—REQUIRED NONRESIDENTIAL MECHANICAL SYSTEM ACCEPTANCE

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

  Exception to Section 120.5: Systems serving healthcare facilities.

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

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

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

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

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

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

  6. Supply fan variable flow controls shall be tested in accordance with NA7.5.6.
• CMC § 1104.0. Medium relevance — show source text

  4 only|Any|Any| |E|Group A1 or A2L4 only|Any|Any| |F-1|Group A12 or A2L2,4 only|Any|Any| |F-2|Any2|Any|Any| |H-1|Any|Any|Any| |H-2|Any|Any|Any| |H-3|Any|Any|Any| |H-4|Group A1 or A2L4 only|Any|Any| |H-5|Group A1 or A2L4 only|Any|Any| |I-1|None|Any|Any| |I-2|Group A1 or A2L4 only|Any|Any| |I-3|None|Any|Any| |I-4|Group A1 or A2L4 only|Any|Any| |M|Group A12 or A2L2,4 only|Any|Any| |R-1|Group A1 or A2L4 only|Any|Any| |R-2|Group A1 or A2L4 only|Any|Any| |R-3|Group A1 or A2L4 only|Any|Any| |R-4|Group A1 or A2L4 only|Any|Any| |S-1|Group A12 or A2L2,4 only|Any|Any| |S-2|Any2|Any|Any| |U|Any|Any|Any|

  Notes: 1 See Section 1104.0. 2 A refrigerant shall be permitted to be used within a high-probability system where the room or space is in accordance with Section 1104.4. 3 Occupancy classifications are defined in the building code. 4 See Section 1104.6 for requirements applicable to A2L equipment.

  independent circuit of high-probability systems shall not exceed the amounts shown in Table 1102.3, except as provided in Section 1104.3, Section 1104.4, and Section 1104.6. The volume of occupied space shall be determined in accordance with Section 1104.2.1 through Section 1104.2.3. Exceptions: (1) Listed equipment in locations other than public corridors and lobbies containing not more than 6.6 pounds (2.99 kg) of refrigerant, regardless of its refrigerant safety classification, provided the equipment is installed in accordance with the listing and with the manufacturer’s installation instructions.

  (2) Listed equipment for use in laboratories with more than 100 square feet (9.29 m [2] ) of space per person, regardless of the refrigerant safety classification, provided that the equipment is installed in accordance with the listing and the manufacturer’s installation instructions. {ASHRAE 15:7.2}

  1104.2.1 Volume Calculations. The volume used to convert from refrigerant concentration limits to refrigerating system quantity limits for refrigerants in Section 1104.2 shall be based on the volume of space to which refrigerant disperses in the event of a refrigerant leak.

  [ASHRAE 15:7.3]