CMC · California Mechanical Code
When do Chapter 5 exhaust provisions apply?
If you’re installing a mechanical exhaust system for bathrooms, kitchens, dryers, or product‑handling, CMC Chapter 5 governs the ductwork, hood types and terminations — but not smoke‑control systems required by the Building/Fire Code. Check Chapter 4 for ventilation rates and Chapter 5 for exhaust construction, hood (Type I/II) rules and makeup‑air/termination details.
Last reviewed: July 6, 2026
What the code requires — plain English (controlling §)
Chapter 5 of the California Mechanical Code (CMC) applies when you are installing, designing, or terminating mechanical exhaust systems — including environmental air exhaust ducts (bathrooms, kitchens, dryer vents), product‑conveying exhausts, and commercial hoods. The CMC describes Chapter 5 as the chapter that “regulates the minimum requirements for exhaust systems” and divides the chapter into environmental/product exhaust (Part I) and commercial hoods/kitchen ventilation (Part II).
Bold note on the user‑requested controlling sections: I attempted to locate the exact text for § 501.0 and § 501.1 in the supplied files but the verbatim sections § 501.0 and § 501.1 of the CMC were not present in the retrieved CMC files. Below I synthesize the applicable scope and application of Chapter 5 using the CMC Chapter 5 text and closely related CMC/Fire Code excerpts that are present in the supplied files.
The single most important rule: Chapter 5 applies to mechanical exhaust systems that move environmental air or product exhaust (including Type I/II kitchen hoods); it does not govern mechanical smoke‑control systems, which are treated separately.
Requirements in detail
1) What Chapter 5 covers (high level)
- Environmental air ducts — exhaust ducts that carry air from domestic kitchens, bathrooms, shower rooms, locker rooms, janitor’s closets, clothes dryers, etc.
- Product‑conveying ducts — systems that convey nonabrasive, moderately abrasive or highly abrasive product exhausts (sawdust, metal dusts, acid vapors, etc.).
- Commercial hoods / kitchen ventilation — Type I (grease, smoke) and Type II (steam, heat, odors) hood systems and the fire‑safety design details that accompany them (Part II).
2) What Chapter 5 does NOT cover (exceptions)
- Smoke‑control systems required by the Building/Fire Code are not treated as Chapter 5 exhaust systems; the Fire Code explicitly states mechanical smoke control systems are not considered exhaust systems under CMC Chapter 5. If you are designing a smoke control system, follow the Building/Fire Code smoke control provisions, not CMC Chapter 5.
3) Where kitchen hoods fit (Type I vs Type II)
- Type I hoods (grease/smoke) are covered by Chapter 5 Part II and require the fire‑safety/grease‑removal and duct construction provisions in that part. Type II hoods (steam/heat/odors) are addressed with separate duct construction and termination rules (e.g., Type II ducts must be rigid metallic; rooftop terminations directed away from roof surfaces; makeup air requirements cross‑reference Section 511.3).
Decision matrix — when Chapter 5 applies
| Decision dimension | Decision value / threshold | Applies (Y/N) | Code Reference |
|---|---|---|---|
| Exhaust source = bathroom, kitchen, clothes dryer, janitor’s closet | Any typical domestic/commercial environmental source | Y | CMC Chapter 5 description (Chapter scope) |
| Exhaust conveys product/particulates (sawdust, metal dust) | Product‑conveying duct systems | Y (special construction/cleanout rules apply) | CMC Chapter 5 description (product‑conveying) |
| Exhaust = commercial cooking producing grease/smoke | Type I hood above grease producing equipment | Y (Part II — Type I hood rules) | CMC Chapter 5 Part II / Type I hood references |
| Exhaust = steam/heat/odors (no grease/smoke) | Type II hood | Y (different duct construction & termination rules) | CMC §519.4–519.7 (Type II hood provisions) |
| System is a mechanical smoke‑control system (for egress/smoke management) | Smoke control required by Building/Fire Code | N — not Chapter 5; follow smoke control requirements | Fire Code: mechanical smoke control not an exhaust system under CMC Chapter 5 |
| Makeup air or termination details | Applies when exhaust causes negative pressurization or per hood makeup requirements | Y (CMC cross‑references makeup air rules) | CMC Type II termination & makeup air references (e.g., §519.6, §519.5) |
4) Interactions with other codes/chapters you must check
- Chapter 4 (Ventilation Air) sets ventilation rates and local‑exhaust rationale — Chapter 5 covers how that exhaust is carried/terminated. See the CMC Chapter 4 / Chapter 5 relationship.
- Building and Fire Codes may call out CMC Chapter 5 for specific terminations/requirements (for example, building codes reference Chapter 5 for environmental duct provisions; Fire Code treats smoke control separately).
Exceptions & special cases
- Mechanical smoke‑control systems required for means‑of‑egress or building smoke management are not governed by Chapter 5; follow Building/Fire Code smoke control chapters.
- Where the CMC or adopting‑agency matrix shows partial adoption or amendments of Chapter 5, specific sections may be adopted or omitted by an authority (check the matrix for your authority). The CMC includes a matrix showing how adopting agencies take on Chapter 5 sections.
- Some exhausts may be allowed to recirculate if the air meets cleaning/class criteria (see CMC cross‑references on recirculation and Section 403.9 criteria).
Common mistakes
- Treating a smoke‑control system as a Chapter 5 exhaust system — this is wrong. Smoke control is separate under the Building/Fire Code.
- Assuming all hoods are Type I — if the source only produces steam/heat/odors (no grease), the hood may be Type II and different duct/termination rules apply.
- Forgetting makeup air — high volume exhaust (commercial hoods, large dryers) often requires makeup air per the CMC; neglecting makeup air can create combustion/pressurization issues.
- Confusing ventilation rate requirements (Chapter 4) with exhaust system construction/termination (Chapter 5). Rates are set in Chapter 4; Chapter 5 tells you how to route/terminate and what construction standards apply.
Worked example — concrete scenario
Scenario: A small restaurant installs a four‑burner gas range in a 600 ft² kitchen that produces grease and smoke. The owner asks: do Chapter 5 exhaust provisions apply and what must be considered?
Do Chapter 5 rules apply?
- Yes. This is a commercial cooking operation producing grease and smoke, so a Type I hood and its exhaust system fall squarely under CMC Chapter 5 (Part II).
What specific Chapter 5 concerns will the designer check?
- Hood type and capture/containment (Type I required for grease/smoke).
- Duct construction: follow the rigid/grease‑resistant duct requirements for Type I hoods (see the Chapter 5 Part II hood/duct rules).
- Termination location: rooftop termination direction/clearances per Chapter 5 hood termination rules.
- Makeup air: provide makeup air sized and interlocked as required so the exhaust does not create unsafe negative pressure inside the building (CMC cross‑references makeup air, e.g., §511.3).
Example numbers (illustrative only — designer must calculate per code and manufacturer):
- Typical commercial cooking hood exhaust could be several hundred to several thousand CFM depending on equipment and hood capture. Provide makeup air equal to or interlocked with the hood exhaust per CMC/energy code guidance. (Specific CFM calculations and Table references are in the ventilation/hood design guidance and CMC hood sections — see Chapter 4 for rates and Chapter 5 hood details).
Related provisions (pull these when you design or permit)
- § 403.9 — Recirculation/air cleaning criteria (when exhaust may be cleaned and recirculated).
- § 511.3 — Makeup air requirements referenced by hood exhaust provisions (see Type II/hood sections).
- § 519.4 – § 519.7 — Type II hood exhaust construction, termination and makeup‑air cross‑references.
- Chapter 4 (Ventilation Air) — ventilation rates and the role of local exhaust (Chapter 5 implements the exhaust system requirements).
- Fire Code §909.x / building code smoke control provisions — for distinguishing smoke control systems from Chapter 5 exhaust systems.
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 427.2.3 High relevance — show source text
[F] 427.2.3 Gas cabinets. Gas cabinets shall be constructed in accordance with Section 5003.8.6 of the California Fire Code and shall comply with the following:
Cabinets shall be exhausted to the exterior through a dedicated exhaust duct system installed in accordance with Chapter 5 of the California Mechanical Code .
Supply and exhaust ducts shall be enclosed in a 1-hour rated shaft enclosure from the cabinet to the exterior. The average velocity of ventilation at the face of access ports or windows shall be not less than 200 feet per minute (1.02 m/s) with a minimum of 150 feet per minute (0.76 m/s) at any point of the access port or window.
Cabinets shall be provided with an automatic sprinkler system internal to the cabinet.
SECTION 435 — SPECIAL PROVISIONS FOR LICENSED 24-HOUR CARE FACILITIES IN A GROUP R-2.1, R-3.1, R-4 [SFM]
435.1 Scope. The provisions of this section shall apply to 24-hour care facilities in a Group R-2.1, R-3.1 or R-4 occupancy licensed by a governmental agency.
435.2 General. The provisions in this section shall apply in addition to general requirements in this code.
435.2.1 Restraint shall not be practiced in a Group R-2.1, R-3.1 or R-4 Occupancies.
Exception: Occupancies which meet all the requirements for a Group I-3 Occupancy.
435.2.2 Pursuant to Health and Safety Code Section 13133, regulations of the state fire marshal pertaining to occupancies classified as Residential Facilities (RF) and Residential Care Facilities for the Elderly (RCFE) shall apply uniformly throughout the state and no city, county, city and county, including a charter city or charter county, or fire protection district shall adopt or enforce any ordinance or local rule or regulation relating to fire and panic safety which is inconsistent with these regulations. A city, county, city and county, including a charter city or charter county may pursuant to Health and Safety Code Section 13143.5, or a fire protection district may pursuant to Health and Safety Code Section 13869.7, adopt standards more stringent than those adopted by the state fire marshal that are reasonably necessary to accommodate local climate, geological or topographical conditions relating to roof coverings for Residential Care Facilities for the Elderly.
Exception: Local regulations relating to roof coverings in facilities licensed as a residential care facility for the elderly (RCFE) per Health and Safety Code Section 13133.
435.3 Building height and area provisions.
435.3.1 Group R-2.1, R-3.1 and R-4 shall be constructed in accordance with Table 504.3.
435.3.2 Limitations six or less clients. Group R-3.1 occupancies where nonambulatory clients are housed above the first story, having more than two stories in height or having more than 3,000 square feet (279 m [2] ) of floor area above the first story shall not be of less than one-hour fire-resistance-rated construction throughout.
In Group R3.1 occupancies housing a bedridden client, the client sleeping room shall not be located above or below the first story.
CMC § 2025 Medium relevance — show source text
The building’s structural stability is protected by the regulations for cutting and notching of structural members.
Chapter 4 Ventilation Air. Chapter 4 regulates the minimum requirements for ventilation air supply, exhaust, and makeup air for occupiable spaces within a building. Building ventilation is one important factor affecting the relationship between airborne transmission of respiratory infections and the health and productivity of workers. Ventilation air may be composed of mechanical or natural ventilation, infiltration, recirculated air, transfer air, or a suitable combination of these. Providing a comfortable and healthy indoor environment for building occupants is of primary concern. When determining ventilation rates, typical and unusual significant sources of indoor pollution need to be controlled. Areas such as kitchens, bathrooms, and laundries are all built to allow specific functions. These spaces produce pollutants such as moisture, odors, volatile organic compounds, particles, or combustion byproducts. The purpose of local exhaust is to control concentrates of these pollutants in the room into which they were emitted and to reduce the spread of pollutants into other parts of the occupancy. Local exhaust ventilation is the source control for pollution that is expected in certain rooms. Using local exhaust to extract contaminants before they mix with the indoor environment is essential.
Chapter 5 Exhaust Systems. Chapter 5 regulates the minimum requirements for exhaust systems. Chapter 5 contains two parts: Part I provides exhaust requirements for environmental air ducts and product conveying systems; Part II provides exhaust requirements for commercial hoods and kitchen ventilation. Environmental air ducts include exhaust ducts used for transporting the air from domestic kitchens, bathrooms, shower rooms, locker rooms, janitor’s closets, and clothes dryers. Systems that carry nonabrasive exhaust, such as smoke, moderate abrasives such as sawdust, and high abrasives such as manganese or acid vapors use product-conveying ducts. Part II provides the minimum fire safety requirements related to the design, installation, inspection, and maintenance of grease-type operations, such as cooking, for both fuel-gas and solid fuel. Cooking produces a significant amount of smoke, fumes, vapors, heat, and other pollutants. Therefore, acceptable kitchen ventilation is necessary to prevent fires from the build-up of grease and to provide the occupants protection from smoke, unpleasant odors, pollutants, and dangerous gases. There are two types of exhaust hoods (Type I and Type II) used in commercial kitchen applications.
xiv 2025 CALIFORNIA MECHANICAL CODE
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FORMAT OF THE UNIFORM MECHANICAL CODE
Type I hoods are intended to be installed above equipment or appliances that generate grease or smoke. Type II hoods are intended to be installed above equipment or appliances that generate steam, vapor, heat, or odors and do not generate grease or smoke.
Chapter 6 Duct Systems. Chapter 6 regulates requirements for ducts and plenums that are portions of a heating, cooling, ventilation, or exhaust system. This chapter contains material and installation requirements for metal, gypsum, factory-made, flexible, and plastic ducts. It also contains provisions for duct insulation, dampers, fire protection, and automatic shutoff for the building’s air distribution system. It is worth noting that exhaust ducts are regulated by Chapter 5, and combustion air ducts are regulated by Chapter 7.
California Mechanical Code Medium relevance — show source text
A mechanical code, as with any other code, is intended to be adopted as a legally enforceable document to safeguard health, safety, property, and public welfare. The code cannot be effective without satisfactory provisions for its administration and enforcement. The Authority Having Jurisdiction is to review the proposed and completed work and decide whether a mechanical system conforms to the code requirements. As a public servant, the Authority Having Jurisdiction enforces the code in an unbiased proper manner. The design professional is responsible for the design of a safe mechanical system. The contractor is responsible for installing the system in accordance with the plans.
Chapter 2 Definitions. To maintain consistency and encourage the use of common terminology, Chapter 2 establishes definitions to provide clarity of terms and promote the use of a common language throughout the code. Understanding definitions within the context of their application enables greater collaboration, efficiency, standardization, and interpretation in applying and enforcing terms used throughout the code. Codes are technical documents, and every term can impact the meaning of the code text. Terms not defined have a normally accepted meaning.
Chapter 3 General Regulations. Chapter 3 regulates the general requirements, not specific to other chapters, for installing mechanical systems. Many regulations are not specific mechanical requirements but relate to the overall mechanical system. This chapter contains safety requirements for appliance location and installation, appliance and system access, condensate disposal, clearances to combustibles, and return or outside air used in mechanical systems. Listing method of approval, based on applicable nationally recognized standards for the safe and proper installation of mechanical systems, is essential to ensure protection of public health, safety, and welfare. These safety requirements provide protection for piping, tubing, materials, and structures, including provisions for installation practices addressing stress and strain, sleeving, and hanger support. The building’s structural stability is protected by the regulations for cutting and notching of structural members.
Chapter 4 Ventilation Air. Chapter 4 regulates the minimum requirements for ventilation air supply, exhaust, and makeup air for occupiable spaces within a building. Building ventilation is one important factor affecting the relationship between airborne transmission of respiratory infections and the health and productivity of workers. Ventilation air may be composed of mechanical or natural ventilation, infiltration, recirculated air, transfer air, or a suitable combination of these. Providing a comfortable and healthy indoor environment for building occupants is of primary concern. When determining ventilation rates, typical and unusual significant sources of indoor pollution need to be controlled. Areas such as kitchens, bathrooms, and laundries are all built to allow specific functions. These spaces produce pollutants such as moisture, odors, volatile organic compounds, particles, or combustion byproducts. The purpose of local exhaust is to control concentrates of these pollutants in the room into which they were emitted and to reduce the spread of pollutants into other parts of the occupancy. Local exhaust ventilation is the source control for pollution that is expected in certain rooms. Using local exhaust to extract contaminants before they mix with the indoor environment is essential.
Chapter 5 Exhaust Systems. Chapter 5 regulates the minimum requirements for exhaust systems. Chapter 5 contains two parts: Part I provides exhaust requirements for environmental air ducts and product conveying systems; Part II provides exhaust requirements for commercial hoods and kitchen ventilation. Environmental air ducts include exhaust ducts used for transporting the air from domestic kitchens, bathrooms, shower rooms, lo
CMC § 427.2.2 Medium relevance — show source text
One vent shall be within 6 inches (152 mm) of the floor and one shall be within 6 inches (152 mm) of the ceiling. Rooms shall be provided with not fewer than one automatic fire sprinkler to provide container cooling in case of fire.
[F] 427.2.2 One-hour interior room. Where an exterior wall cannot be provided for the room, a 1-hour interior room shall be provided and shall be a room or enclosure separated from the remainder of the building by fire barriers constructed in accordance with Section 707 or horizontal assemblies constructed in accordance with Section 711, or both, with a fire-resistance rating of not less than 1 hour. Openings between the room or enclosure and interior spaces shall be provided with self-closing smoke- and draft-control assemblies having a fire protection rating of not less than 1 hour. An automatic sprinkler system shall be installed within the room. The room shall be exhausted through a duct to the exterior. Supply and exhaust ducts shall be enclosed in a 1hour rated shaft enclosure from the room to the exterior. Approved mechanical ventilation shall comply with the California
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SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY AND USE
Mechanical Code and be provided with a minimum rate of 1 cubic foot per minute per square foot (0.00508 m [3] /s/m [2] ) of the area of the room.
[F] 427.2.3 Gas cabinets. Gas cabinets shall be constructed in accordance with Section 5003.8.6 of the California Fire Code and shall comply with the following:
Cabinets shall be exhausted to the exterior through a dedicated exhaust duct system installed in accordance with Chapter 5 of the California Mechanical Code .
Supply and exhaust ducts shall be enclosed in a 1-hour rated shaft enclosure from the cabinet to the exterior. The average velocity of ventilation at the face of access ports or windows shall be not less than 200 feet per minute (1.02 m/s) with a minimum of 150 feet per minute (0.76 m/s) at any point of the access port or window.
Cabinets shall be provided with an automatic sprinkler system internal to the cabinet.
SECTION 435 — SPECIAL PROVISIONS FOR LICENSED 24-HOUR CARE FACILITIES IN A GROUP R-2.1, R-3.1, R-4 [SFM]
435.1 Scope. The provisions of this section shall apply to 24-hour care facilities in a Group R-2.1, R-3.1 or R-4 occupancy licensed by a governmental agency.
435.2 General. The provisions in this section shall apply in addition to general requirements in this code.
435.2.1 Restraint shall not be practiced in a Group R-2.1, R-3.1 or R-4 Occupancies.
Exception: Occupancies which meet all the requirements for a Group I-3 Occupancy.
CMC § 403.9 Medium relevance — show source text
2 Where combustion equipment is intended to be used on the playing surface, additional dilution ventilation, source control, or both shall be provided. 3 Exhaust shall not be required where two or more sides compose walls that are at least 50 percent open to the outside. 4 Rate is per water closet, urinal, or both. Provide the higher rate where periods of heavy use are expected to occur. The lower rate shall be permitted to be used otherwise. 5 Rate is for a toilet room intended to be occupied by one person at a time. For continuous system operation during hours of use, the lower rate shall be permitted to be used. Otherwise the higher rate shall be used. 6 See other applicable standards for exhaust rate. 7 For continuous system operation, the lower rates shall be permitted to be used. Otherwise the higher rate shall be used. 8 Exhaust air that has been cleaned to meet Class 1 criteria from Section 403.9 shall be permitted to be recirculated. 9 Rate is per showerhead. 10 [HCD 1 & HCD 2] A bathroom is any room containing a bathtub, a shower, a spa, or a similar source of moisture. 11 [HCD 1 & HCD 2] ANSI/ASHRAE 62.2: Tables 5.1 and 5.2.
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CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE
CHAPTER 5 – EXHAUST SYSTEMS
(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
Adopting Agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC Adopting Agency BSC BSC-
CGSFM 1 2 1-AC AC ** SS** ** SS/CC** 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6 Adopt Entire Chapter X X X X X X Adopt Entire Chapter as
amended (amended sections
listed below)X X X X X X X Adopt only those sections
that are listed belowX Chapter/Section 504.1. CMC § 907.8.4 Medium relevance — show source text
907.8.4 Inspection, testing and maintenance. The building owner shall be responsible to maintain the fire and life safety systems in an operable condition at all times. Service personnel shall meet the qualification requirements of NFPA 72 for inspection, testing and maintenance of such systems. Records of inspection, testing and maintenance shall be maintained.
907.9 Where required in existing buildings and structures. An approved fire alarm system shall be provided in existing buildings and structures where required in Chapter 11.
907.10 Smoke alarm maintenance. Smoke alarms shall be tested and maintained in accordance with the manufacturer’s instruc tions and this code.
907.10.1 Smoke alarm replacement. Smoke alarms shall be replaced when any of the following apply:
The smoke alarm fails to respond to operability tests.
The smoke alarm exceeds 10 years from the date of manufacture marked on the unit, unless an earlier replacement is specified in the manufacturer’s instructions.
The smoke alarm end-of-life signal is sounded.
The smoke alarm date of manufacture cannot be determined.
Where the replacement of smoke alarms is required by this section, smoke alarms shall not be required to include the 520-Hz signal unless the smoke alarms to be replaced include that signal.
SECTION 908—EMERGENCY ALARM SYSTEMS
908.1 Group H occupancies. Emergency alarms for the detection and notification of an emergency condition in Group H occupancies shall be provided as required in Chapter 50. 908.2 Group H-5 occupancy. Emergency alarms for notification of an emergency condition in an HPM facility shall be provided as required in Section 2703.12. 908.3 Fire alarm system interface. Where an emergency alarm system is interfaced with a building’s fire alarm system, the signal produced at the fire alarm control unit shall be a supervisory signal. 908.4 Carbon dioxide enrichment systems. A gas detection system shall be provided in rooms and indoor areas in which carbon diox- ide enrichment processes are located in accordance with Section 5307.3.2.
SECTION 909—SMOKE CONTROL SYSTEMS
909.1 Scope and purpose. This section applies to mechanical or passive smoke control systems where they are required for new buildings or portions thereof by provisions of the California Building Code or this code. The purpose of this section is to establish minimum requirements for the design, installation and acceptance testing of smoke control systems that are intended to provide a tenable environment for the evacuation or relocation of occupants. These provisions are not intended for the preservation of contents, the timely restoration of operations or for assistance in fire suppression or overhaul activities. Smoke control systems regulated by this section serve a different purpose than the smoke- and heat-removal provisions found in Section 910. Mechanical smoke control systems shall not be considered exhaust systems under Chapter 5 of the California Mechanical Code .
909.2 General design requirements. Buildings, structures, or parts thereof required by the California Building Code or this code to have a smoke control system or systems shall have such systems designed in accordance with the applicable requirements of Section 909 and the generally accepted and well-established principles of engineering relevant to the design. The construction documents shall include sufficient information and detail to describe adequately the elements of the design necessary for the proper implementation of the smoke control systems. These documents shall be accompanied with sufficient information and analysis to demonstrate compliance with these provisions.
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CMC § 2025 Medium relevance — show source text
Systems that carry nonabrasive exhaust, such as smoke, moderate abrasives such as sawdust, and high abrasives such as manganese or acid vapors use product-conveying ducts. Part II provides the minimum fire safety requirements related to the design, installation, inspection, and maintenance of grease-type operations, such as cooking, for both fuel-gas and solid fuel. Cooking produces a significant amount of smoke, fumes, vapors, heat, and other pollutants. Therefore, acceptable kitchen ventilation is necessary to prevent fires from the build-up of grease and to provide the occupants protection from smoke, unpleasant odors, pollutants, and dangerous gases. There are two types of exhaust hoods (Type I and Type II) used in commercial kitchen applications.
xiv 2025 CALIFORNIA MECHANICAL CODE
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
FORMAT OF THE UNIFORM MECHANICAL CODE
Type I hoods are intended to be installed above equipment or appliances that generate grease or smoke. Type II hoods are intended to be installed above equipment or appliances that generate steam, vapor, heat, or odors and do not generate grease or smoke.
Chapter 6 Duct Systems. Chapter 6 regulates requirements for ducts and plenums that are portions of a heating, cooling, ventilation, or exhaust system. This chapter contains material and installation requirements for metal, gypsum, factory-made, flexible, and plastic ducts. It also contains provisions for duct insulation, dampers, fire protection, and automatic shutoff for the building’s air distribution system. It is worth noting that exhaust ducts are regulated by Chapter 5, and combustion air ducts are regulated by Chapter 7.
Chapter 7 Combustion Air. Chapter 7 regulates combustion air requirements for ventilation and dilution of flue gases for appliances installed in buildings. Fuel-gas appliances not regulated by chapter include direct vent appliances and Type I clothes dryers. Makeup air requirements for Type I clothes dryers are located in Chapter 5. Chapter 7 provides acceptable methods for supplying satisfactory combustion air to ensure proper combustion. Combustion air can be supplied by using indoor combustion air or by introducing the air from the outdoors.
Combustion is the rapid oxidation of fuel to release energy. The oxygen required to release the energy from the fuel normally comes from the air. Incomplete combustion of fuel occurs when inadequate oxygen is provided to the appliance. Combustion is needed to provide ventilation cooling for the casing and internal controls. When a lack of oxygen occurs, some of the carbon is not oxidized, and carbon monoxide forms.
Chapter 8 Chimneys and Vents. Chapter 8 regulates the installation, design, and construction of venting systems for fuel-burning appliances. The provisions addressed within this chapter follow procedures an installer would use to design or evaluate a venting system. Many requirements apply to the design and construction of venting systems, chimneys, installation of gas vents, and the sizing of venting system for a Category I appliance. Sizing venting systems require rigorous engineering calculations. However, the venting sizing requirements and sizing tables in this chapter already perform the calculations for the benefit of the end user.
Combustion appliances produce products of incomplete combustion, including potentially harmful carbon monoxide (CO). It is desirable to vent these products to the outdoors. Although the gas is clean-burning fuel, the products of combustion must not be allowed to collect within a building.
CMC § 1202.5.2 Medium relevance — show source text
1202.5.2 Contaminants exhausted. Contaminant sources in naturally ventilated spaces shall be removed in accordance with the California Mechanical Code and the California Fire Code .
1202.5.2.1 Bathrooms. Rooms containing bathtubs, showers, spas and similar bathing fixtures shall be mechanically ventilated in accordance with the California Mechanical Code .
The minimum exhaust rate shall not be less than that established by Table 403.7 “Minimum Exhaust Rates.” See California Mechanical Code, Chapter 5, for additional provisions related to environmental air ducts.
[HCD 1] In addition to the requirements in this section and in the California Mechanical Code, bathrooms in Group R occupancies shall be mechanically ventilated in accordance with the California Green Building Standards Code (CALGreen), Chapter 4, Division 4.5.
1202.5.3 Openings on yards or courts. Where natural ventilation is to be provided by openings onto yards or courts, such yards or courts shall comply with Section 1205.
1202.6 Other ventilation and exhaust systems. Ventilation and exhaust systems for occupancies and operations involving flammable or combustible hazards or other contaminant sources as covered in the California Mechanical Code or the California Fire Code shall be provided as required by both codes.
SECTION 1203—TEMPERATURE CONTROL
1203.1 Equipment and systems. Interior spaces intended for human occupancy shall be provided with active or passive space heating systems capable of maintaining an indoor temperature of not less than 68°F (20°C) at a point 3 feet (914 mm) above the floor on the design heating day.
Exceptions: 1. Space heating systems are not required for: 1.1. Interior spaces where the primary purpose of the space is not associated with human comfort.
1.2. Group F, H, S or U occupancies. 2. [HCD 1] For limited-density owner-built rural dwellings, a heating facility or appliance shall be installed in each dwelling subject to the provisions of Subchapter 1, Chapter 1, Title 25, California Code of Regulations, commencing with Section 74; however, there shall be no specified requirement for heating capacity or temperature maintenance. The use of solid-fuel or solar-heating devices shall be deemed as complying with the requirements of this section. If nonrenewable fuel is used in these dwellings, rooms so heated shall meet current installation standards. 3. [OSHPD 1, 1R, 2, 3, 4 & 5] Space heating systems shall comply with the requirements of the California Mechanical Code. 4. [HCD 1] When a passive solar energy collector is designed as a conditioned area it shall comply with the California Energy Code. Nonconditioned passive solar energy collectors are exempt from compliance with the California Energy Code.
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INTERIOR ENVIRONMENT
SECTION 1204—LIGHTING
1204.1 General. Every space intended for human occupancy shall be provided with natural light by means of exterior glazed openings in accordance with Section 1204.2 or shall be provided with artificial light in accordance with Section 1204.3. Exterior glazed openings shall open directly onto a public way or onto a yard or court in accordance with Section 1205.
CMC § 1.11. Medium relevance — show source text
The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.
2025 CALIFORNIA EXISTING BUILDING CODE 5A-1
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5 A PRESCRIPTIVE COMPLIANCE METHOD
User notes:
About this chapter: Chapter 5A provides details for the prescriptive compliance method for alteration, addition and change of occupancy of existing buildings and structures regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development, which include hospitals and correctional treatment centers [applications listed in Section 1.10.1 (OSHPD 1)].
SECTION 501 A —GENERAL
501 A .1 Scope. The provisions of this chapter shall control the alteration, addition and change of occupancy of existing buildings and structures. The provisions of this chapter shall apply to existing structures for applications listed in Section 1.10.1 [OSHPD 1] regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Planning and Development (OSHPD).
501 A .1.1 Compliance with other methods. Alterations, additions and changes of occupancy to existing buildings and structures shall comply with the provisions of this chapter or with one of the methods or procedures provided in Section 301 A .3.
501 A .2 Fire-resistance ratings. Fire-resistance ratings shall comply with the California Building Standards Code.
501A.3 Prescriptive compliance provisions. Alterations, additions and changes of occupancy to the following categories of existing buildings and structures shall comply with the provisions of this section.
501A.3.1 Prescriptive compliance provisions for SPC-4D using the California Building Code, 1980 (CBC 1980). Nonconforming buildings shall satisfy the following requirements: 1. The California Building Code, 1980 (CBC 1980), as used in this chapter, consists of the Uniform Building Code, 1979 (UBC 1979) along with requirements contained in: a) California Code of Regulations, Title 24- Building Standards, dated February 2, 1980 (Revision record for Register 80, No. 5). b) California Code of Regulations, Title 22 – Social Security, dated October 13, 1979 (Revision Record for Register 79, No 41). c) California Code of Regulations, Title 17 – Public Health, dated October 13, 1979 (Revision Record for Register 79, No 41-B). 2. All existing structural elements of Seismic Force Resisting System (SFRS) shall satisfy the detailing requirements in the CBC 1980 or demonstrate that the level of seismic performance is equivalent to that given in the CBC 1980, as determined by the building official. 3. A continuous load path or paths with adequate strength and stiffness to transfer all the forces from the point of origin to final point of resistance shall be justified by analysis. _4.
CMC § 17.4 Medium relevance — show source text
8|17.4|1.5|2.5|3.4|5.1|0.6|1.0|1.3|1.9| |10|7.7|13.1|17.8|26.3|2.3|3.8|5.2|7.7|0.8|1.4|2.0|2.9| |12|10.8|18.4|24.9|NP|3.2|5.4|7.3|10.7|1.2|2.0|2.7|4.0| |14|14.4|24.5|NP|NP|4.2|7.1|9.6|14.3|1.6|2.7|3.6|5.4| |16|18.4|NP|NP|NP|5.4|9.1|12.4|18.3|2.0|3.4|4.7|6.9| |18|22.9|NP|NP|NP|6.7|11.4|15.4|22.7|2.5|4.3|5.8|8.6| |20|27.8|NP|NP|NP|8.1|13.8|18.7|27.6|3.1|5.2|7.0|10.4| |22|NP|NP|NP|NP|9.7|16.5|22.3|NP|3.7|6.2|8.4|12.4| |24|NP|NP|NP|NP|11.4|19.3|26.2|NP|4.3|7.3|9.9|14.6| |26|NP|NP|NP|NP|13.2|22.4|NP|NP|5.0|8.5|11.4|16.9| |28|NP|NP|NP|NP|15.1|25.7|NP|NP|5.7|9.7|13.1|19.4| |30|NP|NP|NP|NP|17.2|NP|NP|NP|6.5|11.0|14.9|22.0| |32|NP|NP|NP|NP|19.4|NP|NP|NP|7.3|12.4|16.8|24.8| |34|NP|NP|NP|NP|21.7|NP|NP|NP|8.2|13.9|18.8|NP| |36|NP|NP|NP|NP|24.1|NP|NP|NP|9.1|15.4|20.9|NP| |For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
NP = Not Permitted. Pressure loss exceeds reasonable limits.
a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
100 feet.
c. Flow rate from Section P2904.4.2.CMC § 8.1 Medium relevance — show source text
8.1_ –504.8.2|||X||||||||||||||||||||| |504.9|||X||||||||||||||||||||| |504.9.1 –504.9.3|||X||||||||||||||||||||| |504.10.1 – 504.10.3|||X||||||||||||||||||||| |504.11 – 504.11.1|||X||||||||||||||||||||| |504.11.2 –504.11.6|||X||||||||||||||||||||| |505 – 506_Reserved_|||X||||||||||||||||||||| |507.1|||X|||||||||||||||||||||
- The California Code of Regulations (CCR), Title 19, Division 1 provisions that are found in the California Wildland-Urban Interface Code are a reprint from the current CCR, Title 19, Division 1 text for the code user’s convenience only. The scope, applicability and appeals procedures of CCR, Title 19, Division I remain the same. The state agency does not adopt sections identified by the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.
The California Code of Regulations (CCR), Title 14, Division 1.5 provisions that are found in the California Wildland-Urban Interface Code are not listed in the Matrix Adoption Tables as they are not within the State Fire Marshal’s authority to adopt. These provisions are a reprint from the current CCR, Title 14, Division 1.5 text for the code user’s convenience only and are identified in the body of the code by square brackets containing references to applicable Title 14 sections.
2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE 5-1
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5-2 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE
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5 SPECIAL BUILDING CONSTRUCTION REGULATIONS
User notes:
About this chapter: Chapter 5 provides regulations that establish minimum standards for the location, design and construction of buildings and structures based on construction within a Fire Hazard Severity Zone or a Wildland-Urban Interface (WUI) Area.
The construction provisions of Chapter 5 are intended to supplement the requirements of the California Building Code and California Residential Code and address mitigation of the unique hazards posed to buildings by wildfire and to reduce the hazards of building fires spreading to wildland fuels. This is accomplished by requiring ignition-resistant construction materials. Construction features regulated include underfloor areas; roof coverings; eaves and soffits; gutters and downspouts; exterior walls, doors and windows; ventilation openings and accessory structures.
SECTION 501—GENERAL
501.1 Scope. Buildings and structures in a wildland-urban interface area shall be constructed in accordance with the California Build- ing Code and this code.
Exceptions:
- Group U accessory structures not exceeding 120 square feet (11 m [2] ) in floor area where located not less than 50 feet (15 240 mm) from applicable buildings.
- Group U agricultural buildings not less than 50 feet (15 240 mm) from applicable buildings.
CMC § 3905.3.2 Medium relevance — show source text
Exception: Where the registered design professional demonstrates that an engineered mechanical exhaust ventilation system design will prevent the maximum concentration of contaminants from exceeding 25 percent of the LEL, the minimum required rate of exhaust shall be reduced in accordance with such engineered system design.
3905.3.2 Extraction processes using compressed asphyxiant or inert gases. Continuous mechanical exhaust ventilation shall be provided where extraction processes use compressed asphyxiant or inert gases. Mechanical exhaust ventilation shall be provided in accordance with Section 5307.2.
3905.3.3 Post-extraction processes using flammable or combustible liquids or gases. Where flammable liquids, combustible liquids heated above their flashpoint, or flammable gases are used in post-extraction processing the room or area shall be provided with continuous mechanical exhaust in accordance with Section 5004.3.
3905.3.4 Interlocks. Interlocks shall be provided where electrical equipment and appliances are used in processes that generate flammable vapors or gases. Such equipment and appliances shall be interlocked with ventilation fans so that the equipment and appliances cannot be operated unless the exhaust ventilation fans are in operation.
2025 CALIFORNIA FIRE CODE 39-5
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39-6 2025 CALIFORNIA FIRE CODE
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CALIFORNIA FIRE CODE – MATRIX ADOPTION TABLE
CHAPTER 40 – STORAGE OF DISTILLED SPIRITS AND WINES
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
Adopting Agency BSC BSC-
CGSFM Col5 HCD Col7 Col8 DSA Col10 OSHPD Col12 Col13 Col14 Col15 Col16 BSCC DPH AGR DWR CEC CA SL SLC Adopting Agency BSC BSC-
CGT-24 T-19* 1 2 1/AC AC SS 1 1R 2 3 4 5 5 5 5 5 5 5 5 5 Adopt Entire Chapter X Adopt Entire Chapter as
amended (amended sections
listed below)Adopt only those sections that
are listed below[California Code of Regulations,
Title 19, Division 1]Chapter / Section CMC § 4.420 Medium relevance — show source text
410|≥4.420|NA|AHRI
550/590| |Water
source
electri-
cally
operated
positive
displace-
ment|<75|≤0.7885
FL
≤0.6316
IPLV.IP|≤0.7875
FL
≤0.5145
IPLV.IP|75/655|NA|NA|NA|≥3.550|NA|NA|NA|6.150|6.150| |Water
source
electri-
cally
operated
positive
displace-
ment|≥75
and
<150|≤0.7579
FL
≤0.5895
IPLV.IP|≤0.7140
FL
≤0.4620
IPLV.IP|54/445|≥4.640|≥3.680|≥2.680|NA|≥8.330|≥6.410|≥4.420|NA|NA| |Water
source
electri-
cally
operated
positive
displace-
ment|≥75
and
<150|≤0.7579
FL
≤0.5895
IPLV.IP|≤0.7140
FL
≤0.4620
IPLV.IP|75/655|NA|NA|NA|≥3.550|NA|NA|NA|6.150|6.150| |Water
source
electri-
cally
operated
positive
displace-
ment|≥150
and
<300|≤0.6947
FL
≤0.5684
IPLV.IP|≤0.7140
FL
≤0.4620
IPLV.IP|54/445|≥4.640|≥3.680|≥2.680|NA|≥8.330|≥6.410|≥4.420|NA|NA| |Water
source
electri-
cally
operated
positive
displace-
ment|≥150
and
<300|≤0.6947
FL
≤0.5684
IPLV.IP|≤0.7140
FL
≤0.4620
IPLV.IP|75/655|NA|NA|NA|≥3.550|NA|NA|NA|6.150|6.150| |Water
source
electri-
cally
operated
positive
displace-
ment|≥300
and
<600|≤0.6421
FL
≤0.5474
IPLV.IP|≤0.6563
FL
≤0.4305
IPLV.IP|54/445|≥4.930|≥3.960|≥2.970|NA|≥8.900|≥6.CMC § 4A-5 Medium relevance — show source text
408A Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-5
CHAPTER 5 PRESCRIPTIVE COMPLIANCE METHOD . . . . . 5-3
501 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
502 Additions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
503 Alterations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
504 Fire Escapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
505 Windows and Emergency Escape Openings . . . . . . . 5-8
506 Change of Occupancy. . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
507 Historic Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
CHAPTER 5A [OSHPD 1] PRESCRIPTIVE COMPLIANCE
METHOD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-3
501A General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-3
502A Additions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-4
503A Alterations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-5
504A Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-7
505A Reserved. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-7
506A Change of Occupancy. . . . . . . . . . . . . . . . . . . . . . . . . . . .5A-7
CHAPTER 6 CLASSIFICATION OF WORK . . . . . . . . . . . . . . . 6-3
CMC § 4A-3 Medium relevance — show source text
CHAPTER 4A [OSHPD 1] REPAIRS . . . . . . . . . . . . . . . . . . . . .4A-3
401A General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3
402A Building Elements and Materials. . . . . . . . . . . . . . . . . .4A-3
403A Fire Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3
404A Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3
405A Structural. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-3
406A Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-4
407A Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-4
408A Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4A-5
CHAPTER 5 PRESCRIPTIVE COMPLIANCE METHOD . . . . . 5-3
501 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
502 Additions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
503 Alterations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
504 Fire Escapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
505 Windows and Emergency Escape Openings . . . . . . . 5-8
506 Change of Occupancy. . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
507 Historic Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
CHAPTER 5A [OSHPD 1] PRESCRIPTIVE COMPLIANCE
CMC § 2.1 Medium relevance — show source text
Exception: The glazed areas shall not be required where artificial light and a local exhaust system are provided. The minimum local exhaust rates shall be 50 cubic feet per minute (25 L/s) for intermittent ventilation or 20 cubic feet per minute (10 L/s) for contin- uous ventilation in accordance with the California Mechanical Code, Chapter 4 . Exhaust air from the space shall be exhausted directly to the outdoors.
R325.2.1 Bathroom exhaust fans. Each bathroom containing a bathtub, shower or tub/shower combination shall be mechanically ventilated for purposes of humidity control in accordance with the California Mechanical Code, Chapter 4; and the California Green Building Standards Code, Chapter 4, Division 4.5.
Note: Window operation is not a permissible method of providing bathroom exhaust for humidity control.
3-72 2025 CALIFORNIA RESIDENTIAL CODE
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BUILDING PLANNING
R325.3 Ventilation. Ventilation air rates shall be in compliance with the California Mechanical Code.
R325.4 Opening location. Outdoor intake and exhaust openings shall be located in accordance with Sections R325.4.1 and R325.4.2.
R325.4.1 Intake openings. Mechanical and gravity outdoor air intake openings shall be located not less than 10 feet (3048 mm) from any hazardous or noxious contaminant, such as vents, chimneys, plumbing vents, streets, alleys, parking lots and loading docks.
For the purpose of this section, the exhaust from dwelling unit toilet rooms, bathrooms and kitchens shall not be considered as hazardous or noxious.
Exceptions:
The 10-foot (3048 mm) separation is not required where the intake opening is located 3 feet (914 mm) or greater below the contaminant source.
Vents and chimneys serving fuel-burning appliances shall be terminated in accordance with the applicable provisions of the California Mechanical Code.
Clothes dryer exhaust ducts shall be terminated in accordance with the California Mechanical Code.
R325.4.2 Exhaust openings. Exhaust air shall not be directed onto walkways.
R325.5 Outside opening protection. Air exhaust and intake openings that terminate outdoors shall be protected with corrosionresistant screens, louvers or grilles having an opening size of not less than [1] / 4 inch (6 mm) and a maximum opening size of [1] / 2 inch (13 mm), in any dimension. Openings shall be protected against local weather conditions. Outdoor air exhaust and intake openings shall meet the provisions for exterior wall opening protectives in accordance with this code.
R325.6 Interior stairway illumination. Interior stairways shall be provided with an artificial light source to illuminate the landings and treads. The light source shall be capable of illuminating treads and landings to levels of not less than 1 footcandle (11 lux) as measured at the center of treads and landings. There shall be a wall switch at each floor level to control the light source where the stairway has six or more risers.
Exception: A switch is not required where remote, central or automatic control of lighting is provided.
CMC § 1.5 Medium relevance — show source text
Division 1.5
Section|Title 19,
Division 1
Section|Gov Code
Section|PRC
Section|HSC
Section| |---|---|---|---|---|---|---|---|---|---|---| |Section|Title|Title|Title|Title|Title|Title|Title|Title|Title|Title| |Chapter 4|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements|Wildland-urban interface area requirements| |403.2.5|Address installation,
location, and visibility|Y||||1274.04(a)
1274.04(b)
1274.04(c)
1274.04(d)
1274.04(e)
1274.04(f)||||| |404|Water supply|Y||||1275.02||||| |404.1|General|Y|||507|1275.02(b)||||| |404.2|Required water supply|Y||||1275.02(c)||||| |404.3|Draft sites|Y||||||||| |404.3.1|Access|Y|||507.5.4|||||| |404.3.2|Pumper access points|Y|404.3.2|||||||| |404.4|Hydrants|Y|||507.5|||||| |404.5|Adequate water
supply|Y|||507.3|1275.02(b)||||| |404.6|Reserved|N||||||||| |404.7|Obstructions|Y|||507.5.4|||||| |404.8|Identification|Y||||1275.04(a)||||| |404.9|Testing and
maintenance|Y|||507.5.2|||||| |404.10|Reliability|Y|||507.5.2|||||| |404.10.1|Objective|Y|404.10.1|||||||| |404.10.2|Clearance of fuel|Y|||4907.1|||||| |404.10.3|Standby power|Y|||507.5.2|||||| |Chapter 5|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations|Special building construction regulations| |501|General|Y||701A||||||| |501.1|Scope|Y||701A.3||||||| |501.2|Objective|Y||701A.2||||||| |501.3|Fire-resistance-rated
construction|Y||703.2.1.5||||||| |501.4|Noncombustibility
tests|Y||703.3||||||| |501.4.1|Noncombustible
materials|Y||703.3.CMC § 110.2 Medium relevance — show source text
Source leaving liquid temperature.
1. The cooling evaporator liquid flow rate used for the heating rating for a reverse cycle air-to-water heat pump shall be the flow rate determined during the full-load cool-
ing rating.
2. The cooling evaporator liquid flow rate for the simultaneous cooling and heating and heat recovery liquid cooled chilling packages rating shall be the liquid flow rates
from the cooling operation full-load rating.
3. For heating-only fluid-to-fluid chiller packages, the evaporator flow rate obtained with an entering liquid temperature of 54°F and a leaving liquid temperature of 44°F
shall be used.
j. NA means the requirements are not applicable.|a. The size category is the full-load net refrigeration cooling mode capacity, which is the capacity of the evaporator available for cooling of the thermal load external to the chill-
ing package.
b. For air source heat pumps, compliance with both the 47°F and 17°F heating source outdoor air temperature (OAT) rating efficiency is required for heating.
c. Heating full-load rating conditions are at standard rating conditions defined in AHRI 550/590 (I-P), Table 4, which includes the impact of defrost for air source heating ratings.
d. For units that operate in both cooling and heating, compliance with both the cooling and heating efficiency is required.
e. For heat recovery heating chilling package applications where there is simultaneous cooling and heating, compliance with the heating performance heat recover COPHR is
only required at one of the four heating AHRI 550/590 (I-P) standard ratings conditions of Low, Medium, Hot-Water 1 or Hot-Water 2. Compliance with the cooling-only perfor-
mance is required as defined in Notes b and c of Table 110.2-I.
f. For liquid source heat recovery chilling packages that have capabilities for heat rejection to a heat recovery condenser and a tower condenser, the COPHR applies to operation
at full load with 100 percent heat recovery (no tower rejection). Units that only have capabilities for partial heat recovery shall meet the requirements of Table 110.2-D, Water
Chilling Packages—Minimum Efficiency Requirements.
g. For heat recovery heating chilling package applications where there is simultaneous cooling and heating, compliance with the heating performance heat recover COPHR is
only required at one of the four heating AHRI 550/590 (I-P) standard ratings conditions of Low, Medium, Hot-Water 1 or Hot-Water 2. Compliance with the cooling-only perfor-
mance is required as defined in Notes b and c of Table 110.2-I.
h. Water-to-water heat pumps with a capacity less than 135,000 Btu/h are included in Table 110.2-B, Heat Pumps—Minimum Efficiency Requirements.
i. Source leaving liquid temperature.
1. The cooling evaporator liquid flow rate used for the heating rating for a reverse cycle air-to-water heat pump shall be the flow rate determined during the full-load cool-
ing rating.
2. The cooling evaporator liquid flow rate for the simultaneous cooling and heating and heat recovery liquid cooled chilling packages rating shall be the liquid flow rates
from the cooling operation full-load rating.
3. For heating-only fluid-to-fluid chiller packages, the evaporator flow rate obtained with an entering liquid temperature of 54°F and a leaving liquid temperature of 44°F
shall be used.
j. NA means the requirements are not applicable.|a.CMC § 505.2 Medium relevance — show source text
20|||X|||||||||||||||||||||| |504|||X|†|†|†|||||X|X||X|X|||||||||| |505|||X||||||||X|X||X|X|||||||||| |505.2||||X|X|||||||||||||||||||| |506|||||||||||X|X||X|X|||||||||| |506.1 –506.1.1|X||X|||||||||||||||||||||| |506.1.2|||||||||||X|X||X|X|||||||||| |506.2 – 506.3|X||X|||||||||||||||||||||| |506.4|||X|||||||||||||||||||||| |506.5_ Exception_|X|||||||||||||||||||||||| |506.6||||†|†|†|||||||||||||||||||
The state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.
2025 CALIFORNIA EXISTING BUILDING CODE 5-1
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5-2 2025 CALIFORNIA EXISTING BUILDING CODE
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5 PRESCRIPTIVE COMPLIANCE METHOD
User notes:
About this chapter: Chapter 5 provides details for the prescriptive compliance method—one of the three main options of compliance available in this code for buildings and structures undergoing alteration, addition or change of occupancy.
SECTION 501—GENERAL
501.1 Scope. The provisions of this chapter shall control the alteration, addition and change of occupancy of existing buildings and structures, including historic buildings and structures, [BSC] including state-regulated structures in accordance with Section 501.1.2. Historic buildings and structures shall comply with Part 8, Title 24, C.C.R.
Exceptions: 1. [HCD 2] For relocated or moved buildings and maintenance, alteration, repair, addition or change of occupancy to existing buildings and accessory structures in mobilehome parks or special occupancy parks as provided in Section 1.8.2.1.3. See California Code of Regulations, Title 25, Division 1, Chapters 2 and 2.2. 2. [HCD 1] Limited-density owner-built rural dwellings.
[HCD 1] In addition to the requirements in this chapter, maintenance, alteration, repair, addition or change of occupancy to existing buildings and accessory structures under the authority of the Department of Housing and Community Development, as provided in Section 1.8.2.1.1, shall comply with California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1.
501.1.1 Compliance with other methods. Alterations, additions and changes of occupancy to existing buildings and structures shall comply with the provisions of this chapter or with one of the methods provided in Section 301.3.
501.1.2 Existing state-owned structures. [BSC] The provisions of Sections 317 through 322 establish minimum standards for earth- quake evaluation and design for retrofit of existing state-owned structures, including buildings owned by the University of California, the California State University and the Judicial Council.
CMC § 4A-4 Medium relevance — show source text
4A-4 2025 CALIFORNIA EXISTING BUILDING CODE
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REPAIRS
SECTION 408 A —PLUMBING
408 A .1 Materials. Plumbing materials and supplies shall not be used for repairs that are prohibited in the Title 24 Part 5 California Plumbing Code (CPC).
408 A .2 Water closet replacement. The maximum water consumption flow rates and quantities for all replaced water closets shall be 1.28 gallons ( 4.8 L) per flushing cycle.
408 A .3 Health care facilities. Portions of medical gas systems being repaired in Group I-2, ambulatory care facilities and outpatient clinics shall comply with NFPA 99 requirements for repairs.
2025 CALIFORNIA EXISTING BUILDING CODE 4A-5
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4A-6 2025 CALIFORNIA EXISTING BUILDING CODE
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CALIFORNIA EXISTING BUILDING CODE – MATRIX ADOPTION TABLE
CHAPTER 5 – PRESCRIPTIVE COMPLIANCE METHOD
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
Adopting Agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC Adopting Agency BSC BSC-
CGSFM 1 2 1/AC AC SS SS/CC 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6 Adopt Entire Chapter X X Adopt Entire Chapter as
amended (amended
sections listed below)X X X Adopt only those sections
that are listed belowX X X X X X X X Chapter / Section 501 X X X X 501.1 X X X 501.1 –501.3 X 501.1.2 X 501. CMC § 120.10 Medium relevance — show source text
4(f)2 Variable Air volume (VAV) 120.10(a), 140.4(c)2, 140.4(d), 140.9(c)4, 141.0(a)2, 141.0(b)3, 160.2(c)7, 170.2(c)4A, 170.2(c)4B, Table 170.2-B, Table 170.2-C, Table 180.2-D Capacity heat pump (VCHP) 150.1(b)3, 170.1(d)2 Exhaust 140.9(c)3 Flow control 140.4(k)6, 160.3(d), 170.2(c)4I Fluid flow 140.4(k)1, 170.2(c)4I Speed 120.6(a), 120.6(b)5 Speed compressor 120.6(a)3, 120.6(a)7, 150.0(m)13, 160.3(b)5L Speed control 140.4(k)6, 140.9(b) Speed drive 120.6(e), 120.9(b), 140.4(c)1, 140.4(k)6, 160.4(e), 170.2(c)4I Speed fan 120.6(a)4, 120.6(a)8, 120.6(b)1, 150.0(o), 160.2(b)2 Ventilation 150.0(o), 160.2(b)2A Vending Machine 140.6(a)3J, K, L Vent Damper 110.2(d), 110.2(f) Vented Attic 150.0(a), 150.0(g), 150.2(b)1J, 160.1(a), 160.1(d), 180.2(b)1 Vented Range Hood 150.0(o), Table 150.0-E, 150.0(v), 160.2(b)2B, Table 160.2-E Ventilated Attic 150.1(c)9, 170.2(c), 180.2(a)1 Ventilation 120.1, 140.4(b)4, 150.0(o), 160.3(d)2 Air 120.1(d), 120.2(e), 130.1(f), 140.4(e), 140.4(m), 140.9(b), 150.0(o), 150.1(b), 150.2(a)2C, 160.2(b)2B, 160.2(c), 160.5(b), 170.1(d), 170.2(c), 180.1(a), 180.3(a) And indoor air quality 120.1, 150.0(o), 160.2(b)2 Cooling 150.1(b)3, 150.1(c)12, 150.2(a), 170.1(d) Dampers 150.0(m)8, 160.3(b) Device 10-103(b), 120.1(d), 160.2(c)5 Doors 120.6(f) Fan 120.6(f), 150.2(b)1L, 180.2(b) Load 140.4(b)4, 170.2(c) Only 120.1(h)
CMC § 5.2 Medium relevance — show source text
CALIFORNIA GREEN BUILDING STANDARDS CODE – MATRIX ADOPTION TABLE
CHAPTER 5 – NONRESIDENTIAL MANDATORY MEASURES
DIVISION 5.2 – ENERGY EFFICIENCY
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
Adopting agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 OSHPD Col11 Col12 Col13 Col14 Col15 BSCC DPH AGR DWR CEC CA SL SLC Adopting agency BSC BSC-
CGSFM 1 2 1/AC AC SS 1 1R 2 3 4 5 5 5 5 5 5 5 5 5 Adopt entire CA chapter Adopt entire chapter as
amended (amended
sections listed below)Adopt only those sections that
are listed belowX Chapter/Section Division 5.2 X 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE 5-13
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5 NONRESIDENTIAL MANDATORY MEASURES
DIVISION 5.2 – ENERGY EFFICIENCY
SECTION 5.201—GENERAL
5.201.1 Scope. California Energy Code . For the purposes of mandatory energy efficiency standards in this code, the California Energy Commission will continue to adopt mandatory building standards.
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CHAPTER 5 – NONRESIDENTIAL MANDATORY MEASURES
DIVISION 5.3 – WATER EFFICIENCY AND CONSERVATION
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
CMC § 904.3.1 Medium relevance — show source text
10|||X|||||||||||||||||||||| |904.3.1||||X||X||||||||||||||||||| |904.5|||X|||||||||||||||||||||| |904.6|||X|||||||||||||||||||||| |904.7|||X|||||||||||||||||||||| |904.8|||X|||||||||||||||||||||| |904.9|||X|||||||||||||||||||||| |904.10|||X|||||||||||||||||||||| |904.11.3|||X|||||||||||||||||||||| |904.14|||X|||||||||||||||||||||| |904.15|||X|||||||||||||||||||||| |905.1|||X|||||||||||||||||||||| |905.2|||X|||||||||||||||||||||| |905.3|||X|||||||||||||||||||||| |905.3.1|||X|||||||||||||||||||||| |905.3.8|||X|||||||||||||||||||||| |905.3.8.1|||X|||||||||||||||||||||| |905.3.8.2|||X|||||||||||||||||||||| |905.3.9|||X|||||||||||||||||||||| |905.3.10|||X|||||||||||||||||||||| |905.4|||X|||||||||||||||||||||| |905.5|||X|||||||||||||||||||||| |905.7.2|||X|||||||||||||||||||||| |906.1|||X|||||||||||||||||||||| |906.2|||X|||||||||||||||||||||| |Table 906.3(1)|||X|||||||||||||||||||||| |Table 906.3(2)|||X|||||||||||||||||||||| |906.3.2|||X|||||||||||||||||||||| |906.3.4|||X|||||||||||||||||||||| |907.1.2|||X|||||||||||||||||||||| |907.1.3|||X|||||||||||||||||||||| |907.1.4|||X|||||||||||||||||||||| |907.1.5|||X|||||||||||||||||||||| |907.2|||X|||||||||||||||||||||| |907.2.1|||X|||||||||||||||||||||| |907.2.1.1|||X|||||||||||||||||||||| |907.2.1.3|||X|||||||||||||||||||||| |907.2.2|||X|||||||||||||||||||||| |907.2.2.3|||X|||||||||||||||||||||| |907.2.3|||X|||||||||||||||||||||| |907.2.3.1|||X|||||||||||||||||||||| |907.2.3.2|||X|||||||||||||||||||||| |907.2.3.3|||X||||||||||||||||||||||
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CALIFORNIA BUILDING CODE – MATRIX ADOPTION TABLE
CHAPTER 9 – FIRE PROTECTION AND LIFE SAFETY SYSTEMS—continued
CMC § 608.18 Medium relevance — show source text
[M] 608.18 Group A2L and B2L refrigerant. Machinery rooms for Group A2L and B2L refrigerant shall comply with Sections 1106.4.1 through 1106.4.3 of the California Mechanical Code .
608.18.1 Elevated temperatures. Open flame-producing devices or continuously operating hot surfaces over 1,290°F (700°C) shall not be permanently installed in the room.
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BUILDING SERVICES AND SYSTEMS
[M] 608.18.2 Refrigerant detector. In addition to the requirements of Section 1105.3 of the California Mechanical Code, refrigerant detectors shall signal an alarm and activate the ventilation system in accordance with the response time specified in Table 608.18.2.
TABLE 608.18.2—GROUP A2L AND B2L DETECTOR ACTIVATION Col2 Col3 Col4 Col5 ACTIVATION LEVEL MAXIMUM
RESPONSE TIME (seconds)ASHRAE 15
VENTILATION LEVELALARM RESET ALARM TYPE Less than or equal to the OEL in Table 1103.1 of the
California Mechanical Code300 1 Automatic Trouble Less than or equal to the refrigerant concentration level
in Table 1103.1 of the_California Mechanical Code_15 2 Manual Emergency [M] 608.18.3 Mechanical ventilation. The machinery room shall have a mechanical ventilation system complying with ASHRAE 15.
SECTION 609—HYPERBARIC FACILITIES
609.1 General. Hyperbaric facilities shall be inspected, tested and maintained in accordance with NFPA 99.
609.2 Records. Records shall be maintained of all testing and repair conducted on the hyperbaric chamber and associated devices and equipment. Records shall be available to the fire code official.
SECTION 610—CLOTHES DRYER EXHAUST SYSTEMS
610.1 Clothes dryer exhaust duct systems. Clothes dryer exhaust duct systems shall be in accordance with Sections 610.1.1 and 610.1.2.
610.1.1 Installation. Clothes dryer exhaust duct systems shall be installed in accordance with the California Mechanical Code or the International Fuel Gas Code, and the manufacturer’s installation instructions.
610.1.2 Maintenance. The lint trap, mechanical and heating components, and the exhaust duct system of a clothes dryer shall be maintained in accordance with the manufacturer’s operating instructions to prevent the accumulation of lint or debris that prevents the exhaust of air and products of combustion.
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CALIFORNIA FIRE CODE – MATRIX ADOPTION TABLE
CHAPTER 7 – FIRE AND SMOKE PROTECTION FEATURES
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
CMC § 0.0929 Medium relevance — show source text
For SI units: 1 square foot = 0.0929 m [2], 1 cubic foot per minute = 0.0283 m [3] /min, 1 cubic foot per minute = 0.4719 L/s, 1 cubic foot per minute per square foot = 5.08 [(L/s)/m [2] ]
Notes: 1 Stands where engines are run shall have exhaust systems that directly connect to the engine exhaust and prevent escape of fumes. 2 Where combustion equipment is intended to be used on the playing surface, additional dilution ventilation, source control, or both shall be provided. 3 Exhaust shall not be required where two or more sides compose walls that are at least 50 percent open to the outside. 4 Rate is per water closet, urinal, or both. Provide the higher rate where periods of heavy use are expected to occur. The lower rate shall be permitted to be used otherwise. 5 Rate is for a toilet room intended to be occupied by one person at a time. For continuous system operation during hours of use, the lower rate shall be permitted to be used. Otherwise the higher rate shall be used. 6 See other applicable standards for exhaust rate. 7 For continuous system operation, the lower rates shall be permitted to be used. Otherwise the higher rate shall be used. 8 Exhaust air that has been cleaned to meet Class 1 criteria from Section 403.9 shall be permitted to be recirculated. 9 Rate is per showerhead. 10 [HCD 1 & HCD 2] A bathroom is any room containing a bathtub, a shower, a spa, or a similar source of moisture. 11 [HCD 1 & HCD 2] ANSI/ASHRAE 62.2: Tables 5.1 and 5.2.
96 2025 CALIFORNIA MECHANICAL CODE
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CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE
CHAPTER 5 – EXHAUST SYSTEMS
(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
CMC § 160.2 Medium relevance — show source text
Table 160.2-F Hood 100.1, 140.9(b), 150.0(o)2B, 160.2(b)2B Makeup air 120.1(c)4, 140.4(o), 150.2(a)1C, 160.2(c)4-5D, 180.1(a)2B, 180.1(b)3B, System 10-103(b), 100.1, 120.1(d)1, 120.1(d)4E, 120.1(f)1, Table 120.1B(A), 140.4(o), 140.9(c)3, 141.1, 150.2(b)1M, 160.2(b)2A, 160.2(b)2A, 160.2(b)2B, 160.2(c)7A, 160.3(a)2E, 160.3(d)2B, 160.5(a)2G Exhaust, Return, Relief, Transfer Fan Power Allowances (Watt/CFM) Table 170.2-C Exhaust, Return, Relief, Transfer Fan Power Allowances (Watts/ CFM) Table 140.4-B Existing Buildings 10-103(a)1C, 10-103(a)2A, 10-103(a)3D, 10-103(d)2, 10-106(a), 10-111(a)2, 100.0(e)3, 100.0(e)4, 100.1, 110.0, 110.8(d), 120.0, 130.0(b),140.0(c), 141.0(b)2D, 141.0(b)2Q, 150.1(b)2, 150.2(a)1, 150.2(a)2BC, 180.1(a)2, 180.2(b)5 Conditions 100.0(a)2, 100.1, 141.0(a)2B, 141.0(b)3B, Table 141.0E, 150.2(b)2B, Table 150.2-D, 180.1(b)2, 180.2(c), 180.3(c)2 Current limiters 110.9(c)3 Duct system 141.0(a), 141.0(b)2D, 141.0(b)2E, 150.2(a), 150.2(b)1D, 150.2(b)1E, 150.2(b)1L, 180.1, 180.2(b)2A, 180.2(b)2B, 180.2(b)5A Efficiency 141.0(b)3D, Table 150.2-D, 180.2(c)
Multifamily buildings 100.0(e)3C, 100.1, 160.5(b), 180.0, 180.1, 180.2 Nonresidential 100.0(e)3A, 120.6(b)1G-H, 120.6(b)2C, 141.0,
141.1
CMC § 519.4 Medium relevance — show source text
519.4 Type II Exhaust Duct Systems. Ducts and plenums serving Type II hoods shall be constructed of rigid metallic materials in accordance with Chapter 6. Duct bracing and supports shall comply with Chapter 6. Ducts subject to positive pressure shall be adequately sealed.
519.5 Termination of Type II Hood Exhaust System. The exhaust system shall terminate in accordance with Section 502.2.2. Rooftop terminations shall be directed away
«
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EXHAUST SYSTEMS
from roof surfaces within 40 inches (1016 mm). The discharge outlet of moisture conveying exhaust ducts, such as dishwasher exhaust ducts, shall not terminate over a public way or over an area where condensate or vapor could create a nuisance or hazard.
519.6 Makeup Air. Makeup air shall be provided in accordance with Section 511.3.
519.7 Independent Exhaust Duct System. Single or combined Type II exhaust systems shall be independent of all other exhaust systems.
2025 CALIFORNIA MECHANICAL CODE 133
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CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE
CHAPTER 6 – DUCT SYSTEMS
(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
Adopting Agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC Adopting Agency BSC BSC-
CGSFM 1 2 1-AC AC ** SS** ** SS/CC** 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6 Adopt Entire Chapter X X X Adopt Entire Chapter as
amended (amended sections
listed below)X X X X X X X X X Adopt only those sections
that are listed belowX Chapter/Section _601.2. CMC § 3905.1.1 Medium relevance — show source text
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
PROCESSING AND EXTRACTION FACILITIES
3905.1.1 Operation. Activation of the gas detection system shall result in all the following:
- Initiation of distinct audible and visual alarm signals in the extraction room.
- Deactivation of all heating systems located in the extraction room.
- Activation of the mechanical ventilation system, where the system is interlocked with gas detection.
- De-energize all light switches and electrical outlets.
3905.1.2 Failure of the gas detection system. Failure of the gas detection system shall result in the deactivation of the heating system; activation of the mechanical ventilation system where the system is interlocked with the gas detection system; and initiation of a trouble signal to sound in an approved location.
3905.2 Emergency shutoff. Extraction processes utilizing gaseous hydrocarbon-based solvents shall be provided with emergency shutoff systems in accordance with Section 5803.1.3.
3905.3 Ventilation. Continuous mechanical exhaust ventilation shall be provided in accordance with Sections 3905.3.1 through 3905.3.4 and Chapter 4 of the California Mechanical Code .
3905.3.1 Extraction processes using flammable or combustible liquids or gases. Continuous mechanical exhaust ventilation shall be provided where extraction processes use flammable or combustible liquids or gases. The mechanical exhaust ventilation shall provide a minimum airflow rate of not less than 5 cfm/ft [2 ] [0.0254 m [3] /(s × m [2] )] of floor area to prevent an accumulation of flammable vapors from exceeding 25 percent of the lower explosive limit (LEL).
Exception: Where the registered design professional demonstrates that an engineered mechanical exhaust ventilation system design will prevent the maximum concentration of contaminants from exceeding 25 percent of the LEL, the minimum required rate of exhaust shall be reduced in accordance with such engineered system design.
3905.3.2 Extraction processes using compressed asphyxiant or inert gases. Continuous mechanical exhaust ventilation shall be provided where extraction processes use compressed asphyxiant or inert gases. Mechanical exhaust ventilation shall be provided in accordance with Section 5307.2.
3905.3.3 Post-extraction processes using flammable or combustible liquids or gases. Where flammable liquids, combustible liquids heated above their flashpoint, or flammable gases are used in post-extraction processing the room or area shall be provided with continuous mechanical exhaust in accordance with Section 5004.3.
3905.3.4 Interlocks. Interlocks shall be provided where electrical equipment and appliances are used in processes that generate flammable vapors or gases. Such equipment and appliances shall be interlocked with ventilation fans so that the equipment and appliances cannot be operated unless the exhaust ventilation fans are in operation.
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CALIFORNIA FIRE CODE – MATRIX ADOPTION TABLE
CHAPTER 40 – STORAGE OF DISTILLED SPIRITS AND WINES
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
CMC § 1305.2.3.3 Medium relevance — show source text
2, 1305.2.3.3, 1305.2.4.1, 1305.2.5, 1305.2.5.1, 1305.2.6, 1305.2.7.1, 1305.2.8, 1305.2.9, 1305.2.9.1, 1305.2.10, 1305.2.10.1, 1305.2.11, 1305.2.11.1, 1305.2.12.1, 1305.2.13, Table 1305.2.15, 1305.2.15.1, 1305.2.16.1, 1305.2.17, 1305.2.17.1, 1305.2.18, 1305.2.18.1, 1305.2.19, Table 1305.2.19, 1305.2.20, 1305.2.20.1, 1307.1.1, 1401.2, 1402.1, 1402.2, 1402.2.1, 1402.3, 1402.4, 1402.5, 1402.6, 1501.5, 1504.1.1, 1504.1.4.1, 1504.1.7, 1509.1, 1509.3, 1510.1
CEC — 25 : California Energy Code
302.2, 702.7, 708.1, 809.1, 907.1, 1104.1
CFC—25: California Fire Code
101.2.2, 101.4.2, 301.3.1, 302.2, 307.1, 308.1, 802.2.1, 802.2.3, 803.2.3, 803.4.1.1, 803.4.1.2, 803.4.1.3, 803.4.1.4, 803.4.1.5, 803.4.1.6, Table 804.5.1.1(1), 904.1.5, 1011.6.1.1, 1303.1.2, 1305.2.8.1, 1305.2.14, 1305.2.14.1, 1401.2, 1501.1, 1501.5, 1502.1, 1502.1.1, 1502.2, 1502.3, 1504.1, 1507.1, 1507.2
CMC—25: California Mechanical Code
302.2, 702.7, 807.1, 902.1.1, 1008.1, 1305.2.7.1, 1305.2.8, 1305.2.8.1
CPC—25: California Plumbing Code
302.2, 408.1, 702.7, 1009.1, 1009.2, 1009.3, 1009.5, 1302.1.6, 1503.1
Frequently asked questions
When exactly should I use Chapter 5 instead of Chapter 4?
Use Chapter 4 to determine ventilation rates (how much air to supply/exhaust). Use Chapter 5 when you are designing or constructing the exhaust ductwork, hoods, terminations, and product‑conveying exhaust systems that carry that air to the outdoors. The CMC describes Chapter 5 as the chapter that regulates minimum requirements for exhaust systems; Chapter 4 sets the ventilation rates.
Are smoke control systems covered by Chapter 5?
No. Mechanical smoke control systems required for egress or smoke management are not considered Chapter 5 exhaust systems; they are covered by Building/Fire Code smoke control chapters.
Does Chapter 5 tell me hood capture/CFM requirements?
Chapter 5 governs hood types, duct construction and termination; hood capture/CFM sizing is done per ventilation/hood performance guidance and referenced standards (Chapter 4 and hood design sections). Use Chapter 4 and the hood sections in Chapter 5 together.
Can I recirculate exhaust air instead of exhausting outdoors?
Only if the CMC or referenced sections permit recirculation and the air meets cleaning/Class criteria (see Section 403.9 criteria referenced in the CMC). If not cleaned to the required class, the exhaust must go outdoors per Chapter 5 rules.
Where can I find the specific duct material and termination rules for Type II hoods?
See the Type II hood provisions (duty material, rooftop termination clearances, makeup air cross‑reference) in the CMC hood sections (e.g., §519.4–519.7).
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