CPC · California Plumbing Code

Dental gas and vacuum systems — emergency shutoffs and alarm differences

For homeowners/patients: Dental offices must have local emergency shutoff valves for oxygen and nitrous oxide that are reachable from each treatment area and clearly labeled. Alarm systems that monitor pressure can be combined into one panel for small dental offices, but alarms must sound and show visual alerts if the main line pressure changes by 20% (and visual alerts stay on until fixed). These requirements come from the California Plumbing Code in **§ 1327.0**, **§ 1327.2**, and **§ 1327.3**.

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Last reviewed: July 6, 2026

What the code requires — 2–4 sentences

The California Plumbing Code requires that dental oxygen and nitrous-oxide piping for Category 2 dental systems include an emergency shutoff valve accessible from all use‑point locations and that warning/alarm systems meet Category 2 alarm rules with a few dental-specific allowances. Key rules are in § 1327.0, § 1327.2, and § 1327.3. The CPC also specifies alarm functions and thresholds (for example, alarm activation at ±20 percent change from normal main‑line pressure) and where pressure sensors must be located relative to shutoff valves.

Emergency shutoff valves for Category 2 dental oxygen and nitrous‑oxide systems must be accessible from every use point in an emergency, labeled for the gas they control, and pressure sensors/alarms must be installed downstream of any emergency shutoff so alarms reflect the patient‑side condition. § 1327.2 and § 1327.3.

Requirements in detail

Key defined terms (first mention)

  • Category 2 — CPC classification for many dental piped gas systems; addressed in Part V rules. § 1327.0.
  • Emergency shutoff valve — a manually accessible valve provided for shutting off oxygen or nitrous oxide to a treatment facility in an emergency. § 1327.2.
  • Warning systems — alarm and monitoring equipment for oxygen and nitrous oxide systems; Category 2 warning systems have special allowances. § 1327.3.

Short bulleted summary of the rules

  • Emergency shutoffs: must be accessible from all use points; one per treatment facility when a central supply serves multiple facilities; labeled for the gas and shut off only the gas they serve. § 1327.2.
  • Remote manifold actuators: a remotely activated shutoff at a manifold is not an acceptable substitute for the required emergency shutoff (and remote actuators must not be of the type that fail‑close on power loss for clinical purposes). § 1327.2(4).
  • Alarm panel: Category 2 warning systems are permitted to be a single alarm panel; alarms must still provide required master/area/local functions per the referenced sections with the dental exceptions. § 1327.3.
  • Alarm functions and thresholds: required alarm types include oxygen/nitrous main‑line low and high pressure and changeover indications; audible/noncancelable visual alarms must activate when main‑line pressure changes 20 percent from normal operating pressure; visual indications must remain until resolved. Pressure switches/sensors must be installed downstream of any emergency shutoff valves and other shutoff valves. § 1327.3 (see detailed items).

Decision‑relevant table

Decision factor Required value / behavior Code Reference
Emergency shutoff accessibility Accessible from all use‑point locations in an emergency § 1327.2(1)
When central supply serves two facilities Each facility must have its own emergency shutoff located in that facility and accessible from its use points § 1327.2(2)
Shutoff labeling & scope Valves must be labeled for the gas controlled and must shut off only the gas to that treatment facility § 1327.2(3)
Remote manifold actuator as emergency shutoff Not permitted to serve as the emergency shutoff; remote actuator design constraints apply (see fail‑open vs fail‑close) § 1327.2(4)
Alarm panel configuration (Category 2) A single alarm panel is permitted, but master/area/local functions still required § 1327.3
Alarm types required Oxygen/N2O main line low, high, and changeover (if automatic) alarms among others § 1327.3(4)
Alarm trip threshold Alarm when main‑line pressure increases or decreases 20 percent from normal operating pressure § 1327.3(5)
Pressure sensor location Downstream of any emergency shutoff or other shutoff valves; sensors must cause alarm if pressure deviates ±20% § 1327.3(7)
Visual/audible behavior Visual stays until resolved; audible may be cancelable but must reinitiate if another alarm occurs § 1327.3(6)–(8)

Exceptions & special cases

  • Remote actuators at a manifold: A remotely activated shutoff at a gas supply manifold is explicitly not acceptable as the required emergency shutoff for Category 2 dental systems. The code also requires that, for clinical purposes, remote actuators must not fail‑close on loss of electric power; if the actuator type is fail‑open, cylinder shutoff valves must be closed when the system is not in use. § 1327.2(4).
  • Single alarm panel allowance: Category 2 warning systems may consolidate master/area/local functions into a single alarm panel, but the panel must still be located where there is continuous surveillance while the facility is in operation and meet the performance requirements otherwise applicable. § 1327.3.
  • The CPC cross‑references broader alarm/performance rules (Category 1/2 requirements) in other sections; where the dental Part V text makes a specific allowance (like the single panel), that allowance supersedes the stricter prescription only to the stated extent. § 1327.3 (references Section 1325.10 / Section 1317.0 applicability).

Common mistakes

  • Installing the pressure sensor upstream of the emergency shutoff so the alarm sees source pressure instead of patient‑side pressure — sensors must be downstream of emergency shutoffs. § 1327.3(7).
  • Using a remote manifold actuator as the only emergency shutoff — the CPC disallows this for the required emergency shutoff. § 1327.2(4).
  • Failing to label shutoff valves for the gas they control or installing a shutoff that shuts multiple gases (shutoffs must only shut the gas for that treatment facility). § 1327.2(3).
  • Silencing visual indicators: visual alarm indications must remain until the cause is resolved — do not design systems where visual indicators auto‑clear without resolution. § 1327.3(6).
  • Overlooking the single‑panel surveillance requirement: when using a single alarm panel, ensure it is located in an area of continuous surveillance while the facility operates. § 1327.3.

Worked example — practical scenario

Scenario: Small dental clinic with two operatories served from a single central oxygen/nitrous manifold in an equipment room.

  1. Emergency shutoffs:

    • Because the central supply serves two treatment facilities, install an emergency shutoff valve in each facility so it is accessible from every use point in that facility. These valves must be labeled “OXYGEN” or “NITROUS OXIDE” as appropriate and must shut off only the gas to that facility. § 1327.2(2)–(3).
    • Do NOT rely on a remotely actuated manifold shutoff in the equipment room as the facility’s emergency shutoff. § 1327.2(4).

  2. Alarm placement and thresholds:

    • Install pressure switches/sensors at the gas source equipment, but ensure pressure sensors that trigger patient‑side alarms are located downstream of the emergency shutoff valves so they monitor the actual patient‑side main line. § 1327.3(7).
    • If the system normal main‑line pressure is 50 psi (example operating pressure), the alarm trip points are ±20 percent: low alarm at 40 psi and high alarm at 60 psi (50 ± 10 psi). The audible/visual alarm behavior follows the code (visual remains until resolved; audible cancelable but must reinitiate on a new alarm). § 1327.3(5)–(6),(8).

  3. Alarm panel:

    • The clinic may use a single alarm panel (combining master/area/local) provided the panel is in an area under continuous surveillance while the clinic operates and still provides the required signals. § 1327.3.

Related provisions

  • § 1327.0 — Part V intro and scope for dental gas and vacuum systems.
  • § 1325.10 — Category 2 warning systems general requirements (cross‑referenced by § 1327.3).
  • § 1317.0 — Master, area, and local alarm system requirements for medical gas and vacuum systems (applies unless otherwise modified).
  • § 1316.2 — Pressure/vacuum indicator locations (relevant to readable indicators at alarm panels and at station outlets).
  • § 1315.0 — Station outlet/inlet requirements (useful when planning shutoffs and downstream sensing).

Code references

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

  • CPC § 1326.6 High relevance — show source text

    1326.6 Station Outlets and Inlets . . . . . . .300

    1326.7 Pressure and Vacuum

    Indicators . . . . . . . . . . . . . . . . . . .300

    1326.8 Warning Systems . . . . . . . . . . . . .300

    1326.9 Distribution . . . . . . . . . . . . . . . . . .300

    1326.10 Labeling and Identification . . . . . .300

    PART V Dental Gas and Vacuum Systems . . . . . . . . . . . . . . . . . . . .300

    1327.0 Dental Gas and Vacuum Systems . . . . . . . . . . . . . . . . . . . .300

    1327.1 General . . . . . . . . . . . . . . . . . . . . .300

    1327.2 Emergency Shutoff Valves (Oxygen and Nitrous Oxide) . . . . .300

    1327.3 Warning Systems (Oxygen and Nitrous Oxide) . . . . . . . . . . . .300

    1327.4 Initial Pressure Test . . . . . . . . . . .301

    1327.5 Maximum Copper Tube Support Spacing . . . . . . . . . . . . . .301

    Table 1327.5 Maximum Copper Tube Support Spacing . . . . . . . . . . . . . .301

    1327.6 Maximum Plastic Pipe Support Spacing . . . . . . . . . . . . . .301

    Table 1327.6 Maximum Plastic Pipe Support Spacing . . . . . . . . . . . . . .301

    1327.7 Standing Pressure Tests for Oxygen and Nitrous Oxide Piping . . . . . . . . . . . . . . . . . . . . . .301

    1327.8 Verifier Operational Pressure Test . . . . . . . . . . . . . . . .302

    CHAPTER 14 FIRESTOP PROTECTION . . . . . .303

    1401.0 General . . . . . . . . . . . . . . . . . . . . .305

    1401.1 Applicability . . . . . . . . . . . . . . . . . .305

    2025 CALIFORNIA PLUMBING CODE xliii

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

    TABLE OF CONTENTS

    1402.0 Construction Documents . . . . . . .305

    1402.1 Penetrations . . . . . . . . . . . . . . . . .305

    1403.0 Installation . . . . . . . . . . . . . . . . . .305

    1403.1 Materials . . . . . . . . . . . . . . . . . . . .305

    1404.0 Combustible Piping Installations . . . . . . . . . . . . . . . . . .305

    1404.1 General Requirements . . . . . . . . .305

    1404.2 Fire-Resistance Rating . . . . . . . . .305

    1404.3 Firestop Systems . . . . . . . . . . . . .305

  • CPC § 1326.9 High relevance — show source text

    1326.9 Distribution. Category 3 systems shall comply with Section 1318.0 through Section 1323.12. [NFPA 99:5.3.10]

    1326.10 Labeling and Identification. Category 3 systems shall comply with Section 1323.13 through Section 1323.15.

    [NFPA 99:5.3.11]

    Part V – Dental Gas and Vacuum Systems.

    1327.0 Dental Gas and Vacuum Systems. 1327.1 General. Dental gas and vacuum systems shall comply with this code and NFPA 99. 1327.2 Emergency Shutoff Valves (Oxygen and Nitrous Oxide).

    (1) All Category 2 medical gas systems shall have an emergency shutoff valve accessible from all use-point locations in an emergency.

    (2) Where a central medical gas supply system supplies two treatment facilities, each facility shall be provided with an emergency shutoff valve located in that treatment facility so as to be accessible from all use-point locations in an emergency.

    (3) Emergency shutoff valves shall be labeled to indicate the gas controlled by the shutoff valve and shall shut off only the gas to the treatment facility that they serve.

    (4) A remotely activated shutoff valve at a gas supply manifold shall not be used for emergency shutoff. For clinical purposes, such a remote valve actuator shall not fail-close in the event of loss of electric power. Where remote actuators are the type that fail-open, it shall be mandatory that cylinder shutoff valves be closed whenever the system is not in use. [NFPA 99:15.4.2.6.1 – 15.4.2.6.4.2]

    1327.3 Warning Systems (Oxygen and Nitrous Oxide). Category 2 warning systems shall comply with Section 1325.10 except as follows:

    (1) Warning systems shall be permitted to be a single alarm panel.

    »

    Part IV – Category 3 Piped Gas and Vacuum Systems.

    1326.0 Category 3 Piped Gas and Vacuum Systems. 1326.1 General. Category 3 piped gas and vacuum systems shall be permitted when all of the following criteria are met:

    (1) Only minimal sedation, as defined in Chapter 2; or no sedation is performed. Deep sedation, moderate sedation, and general anesthesia are not performed.

    (2) The loss of the piped gas and vacuum systems is not likely to cause injury to patients, staff, or visitors, but can cause discomfort.

    (3) The facility piped gas and vacuum systems are intended for Category 3 patient care rooms as defined in Chapter 2. [NFPA 99:5.3.1.2]

    1326.2 Nature of Hazards of Gas and Vacuum Sys- tems. The requirement of Section 1307.2 shall apply to the nature of hazards of gas and vacuum systems. [NFPA 99:5.3.2]

    1326.3 Medical Air Supply Systems. Category 3 central supply systems shall be permitted to consist of the following:

    (1) Gas cylinder or cryogenic liquid container headers in accordance with NFPA 99.

    (2) Oxygen concentrator supply units in accordance with NFPA 99.

    (3) Cylinder manifolds for gas cylinders in accordance with NFPA 99.

    (4) Manifolds for cryogenic liquid containers in accordance with NFPA 99.

  • CPC § 1325.13 High relevance — show source text

    1325.13 Performance Criteria and Testing — Gas, Medical–Surgical Vacuum, and WAGD. Category 2 systems shall comply with Section 1324.0. [NFPA 99:5.2.12]

    2025 CALIFORNIA PLUMBING CODE 299

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

    HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS

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    1326.6 Station Outlets and Inlets. Category 3 systems shall comply with Section 1315.0. [NFPA 99:5.3.5]

    1326.7 Pressure and Vacuum Indicators. Category 3 systems shall comply with Section 1316.2. [NFPA 99:5.3.8] 1326.8 Warning Systems. Warning systems associated with Category 3 systems shall provide the master, area, and local alarm functions of a Category 1 system as required in Section 1317.0, except as follows:

    (1) Warning systems shall be permitted to be a single alarm panel (i.e., a combination master/area alarm panel).

    (2) The alarm panel shall be located in an area of continuous surveillance while the facility is in operation.

    (3) Pressure and vacuum switches/sensors shall be mounted at the source equipment with a pressure indicator at the master alarm panel.

    (4) Electrical power for warning systems shall be in accordance with Section 6.6 of NFPA 99 for Category 3 and Category 4 spaces. [NFPA 99:5.3.9]

    1326.9 Distribution. Category 3 systems shall comply with Section 1318.0 through Section 1323.12. [NFPA 99:5.3.10]

    1326.10 Labeling and Identification. Category 3 systems shall comply with Section 1323.13 through Section 1323.15.

    [NFPA 99:5.3.11]

    Part V – Dental Gas and Vacuum Systems.

    1327.0 Dental Gas and Vacuum Systems. 1327.1 General. Dental gas and vacuum systems shall comply with this code and NFPA 99. 1327.2 Emergency Shutoff Valves (Oxygen and Nitrous Oxide).

    (1) All Category 2 medical gas systems shall have an emergency shutoff valve accessible from all use-point locations in an emergency.

    (2) Where a central medical gas supply system supplies two treatment facilities, each facility shall be provided with an emergency shutoff valve located in that treatment facility so as to be accessible from all use-point locations in an emergency.

    (3) Emergency shutoff valves shall be labeled to indicate the gas controlled by the shutoff valve and shall shut off only the gas to the treatment facility that they serve.

    (4) A remotely activated shutoff valve at a gas supply manifold shall not be used for emergency shutoff. For clinical purposes, such a remote valve actuator shall not fail-close in the event of loss of electric power. Where remote actuators are the type that fail-open, it shall be mandatory that cylinder shutoff valves be closed whenever the system is not in use. [NFPA 99:15.4.2.6.1 – 15.4.2.6.4.2]

  • CPC § 15.4.2.10 High relevance — show source text

    (4) Warning systems for medical gas systems shall provide the following alarms:

    (a) Oxygen main line pressure low.

    (b) Oxygen main line pressure high.

    (c) Oxygen changeover to secondary bank or about to changeover (if automatic).

    (d) Nitrous oxide main line pressure low.

    (e) Nitrous oxide main line pressure high.

    (f) Nitrous oxide changeover to secondary bank or about to changeover (if automatic).

    (5) Audible and noncancelable alarm visual signals shall indicate if the pressure in the main line increases or decreases 20 percent from the normal operating pressure.

    (6) Visual indications shall remain until the situation that caused the alarm is resolved.

    (7) Pressure switches/sensors shall be installed downstream of any emergency shutoff valves and any other shutoff valves in the system and shall cause an alarm for the medical gas if the pressure decreases or increases 20 percent from the normal operating pressure.

    (8) A cancelable audible indication of each alarm condition that produces a sound at the alarm panel shall reinitiate the audible signal if another alarm condition occurs while the audible signal is silenced. [NFPA 99:15.4.2.10]

    1327.4 Initial Pressure Test. Each section of the piping in positive-pressure gas systems and copper vacuum systems shall be pressure tested. Plastic vacuum and plastic scavenging piping shall not be pressure tested. [NFPA 99:15.4.7.4.4.1]

    1327.4.1 Pressure Test. Initial pressure tests shall be conducted as follows:

    (1) After blowdown of the distribution piping

    (2) After installation of station outlet/inlet rough-in assemblies

    (3) Prior to the installation of components of the distribution piping system that would be damaged by the test pressure (e.g., pressure/vacuum alarm devices, pressure/vacuum indicators, and line pressure relief valves) [NFPA 99:15.4.7.4.4.2]

    1327.4.2 Source Shutoff Valve. The source shutoff valve shall remain closed during the pressure tests.

    [NFPA 99:15.4.7.4.4.3]

    1327.4.3 Test Pressure. The test pressure for oxygen and nitrous oxide piping shall be 1.5 times the system operating pressure but not less than a gauge pressure of 150 psi (1035 kPa). [NFPA 99:15.4.7.4.4.4]

    1327.4.4 Examine for Leaks. The test pressure shall be maintained until each joint has been examined for leakage by means of a leak detectant that is safe for use

    with oxygen and does not contain ammonia. [NFPA 99:15.4.7.4.4.5]

    1327.4.5 Leaks Located. Any leaks shall be located, repaired (if permitted), or replaced (if required) by the installer, and retested. [NFPA 99:15.4.7.4.4.6]

    1327.5 Maximum Copper Tube Support Spacing. The maximum support spacing for copper tube shall be in accordance with Table 1327.5. [NFPA 99:15.4.5.6.5]

    TABLE 1327.5

    MAXIMUM COPPER TUBE SUPPORT SPACING

    [NFPA 99: TABLE 15.4.5.6.5]

  • CPC § 1325.7 Medium relevance — show source text

    1325.7 Valves . . . . . . . . . . . . . . . . . . . . . .299

    1325.8 Station Outlets and Inlets . . . . . . .299

    1325.9 Pressure and Vacuum

    Indicators . . . . . . . . . . . . . . . . . . .299

    1325.10 Warning Systems . . . . . . . . . . . . .299

    1325.11 Category 2 Distribution . . . . . . . . .299

    1325.12 Labeling and Identification . . . . . .299

    1325.13 Performance Criteria and Testing — Gas, Medical–Surgical Vacuum, and WAGD . . . . . . . . . . .299

    PART IV Category 3 Piped Gas and Vacuum Systems . . . . . . . . . . . .300

    1326.0 Category 3 Piped Gas and Vacuum Systems . . . . . . . . . . . . .300

    1326.1 General . . . . . . . . . . . . . . . . . . . . .300

    1326.2 Nature of Hazards of Gas and Vacuum Systems . . . . . . . . .300

    1326.3 Medical Air Supply Systems . . . . .300

    1326.4 Medical–Surgical Vacuum Systems . . . . . . . . . . . . . . . . . . . .300

    1326.5 Valves . . . . . . . . . . . . . . . . . . . . . .300

    1326.6 Station Outlets and Inlets . . . . . . .300

    1326.7 Pressure and Vacuum

    Indicators . . . . . . . . . . . . . . . . . . .300

    1326.8 Warning Systems . . . . . . . . . . . . .300

    1326.9 Distribution . . . . . . . . . . . . . . . . . .300

    1326.10 Labeling and Identification . . . . . .300

    PART V Dental Gas and Vacuum Systems . . . . . . . . . . . . . . . . . . . .300

    1327.0 Dental Gas and Vacuum Systems . . . . . . . . . . . . . . . . . . . .300

    1327.1 General . . . . . . . . . . . . . . . . . . . . .300

    1327.2 Emergency Shutoff Valves (Oxygen and Nitrous Oxide) . . . . .300

    1327.3 Warning Systems (Oxygen and Nitrous Oxide) . . . . . . . . . . . .300

    1327.4 Initial Pressure Test . . . . . . . . . . .301

    1327.5 Maximum Copper Tube Support Spacing . . . . . . . . . . . . . .301

    Table 1327.5 Maximum Copper Tube Support Spacing . . . . . . . . . . . . . .301

    1327.6 Maximum Plastic Pipe Support Spacing . . . . . . . . . . . . . .301

    Table 1327.6 Maximum Plastic Pipe Support Spacing . . . . . . . . . . . . . .301

  • CPC § 5.3.3.5 Medium relevance — show source text

    (7) Proportioning air systems in accordance with NFPA 99.

    (8) Medical-surgical vacuum systems in accordance with of NFPA 99.

    (9) Waste anesthetic gas disposal systems (WAGDs) in accordance with NFPA 99.

    (10)Instrument air compressor systems in accordance with NFPA 99. {NFPA 99:5.3.3.5} 1326.4 Medical–Surgical Vacuum Systems. Category 3 systems shall comply with Section 1307.3 through Section 1309.13 and Section 1312.0 through Section 1313.5, except as follows:

    (1) Medical–surgical vacuum systems shall be permitted to be simplex.

    (2) The facility staff shall develop an emergency plan to deal with the loss of medical–surgical vacuum.

    (3) Emergency electrical service shall conform to the requirements of Section 6.6 of NFPA 99 and NFPA 70.

    [NFPA 99:5.3.3.7]

    1326.5 Valves. Category 3 systems shall comply with Section 1314.0. [NFPA 99:5.3.4]

    300 2025 CALIFORNIA PLUMBING CODE

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    HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS

    (2) The alarm panel shall be located in an area of continuous surveillance while the facility is in operation.

    (3) Pressure and vacuum switches/sensors shall be mounted at the source equipment with a pressure indicator at the master alarm panel.

    (4) Warning systems for medical gas systems shall provide the following alarms:

    (a) Oxygen main line pressure low.

    (b) Oxygen main line pressure high.

    (c) Oxygen changeover to secondary bank or about to changeover (if automatic).

    (d) Nitrous oxide main line pressure low.

    (e) Nitrous oxide main line pressure high.

    (f) Nitrous oxide changeover to secondary bank or about to changeover (if automatic).

    (5) Audible and noncancelable alarm visual signals shall indicate if the pressure in the main line increases or decreases 20 percent from the normal operating pressure.

    (6) Visual indications shall remain until the situation that caused the alarm is resolved.

    (7) Pressure switches/sensors shall be installed downstream of any emergency shutoff valves and any other shutoff valves in the system and shall cause an alarm for the medical gas if the pressure decreases or increases 20 percent from the normal operating pressure.

    (8) A cancelable audible indication of each alarm condition that produces a sound at the alarm panel shall reinitiate the audible signal if another alarm condition occurs while the audible signal is silenced. [NFPA 99:15.4.2.10]

    1327.4 Initial Pressure Test. Each section of the piping in positive-pressure gas systems and copper vacuum systems shall be pressure tested. Plastic vacuum and plastic scavenging piping shall not be pressure tested. [NFPA 99:15.4.7.4.4.1]

    1327.4.1 Pressure Test. Initial pressure tests shall be conducted as follows:

    (1) After blowdown of the distribution piping

    (2) After installation of station outlet/inlet rough-in assemblies

  • CPC § 5.2.3.7 Medium relevance — show source text

    (2) The facility staff shall develop their emergency plan to deal with the loss of medical-surgical vacuum. [NFPA 99:5.2.3.7]

    1325.7 Valves. Category 2 systems shall comply with Section 1314.0 through Section 1314.12.1. [NFPA 99:5.2.4]

    1325.8 Station Outlets and Inlets. Category 2 systems shall comply with Section 1315.0. [NFPA 99:5.2.5]

    1325.9 Pressure and Vacuum Indicators. Category 2 systems shall comply with Section 1316.2. [NFPA 99:5.2.8]

    1325.10 Warning Systems. Warning systems associated with Category 2 systems shall provide the master, area, and local alarm functions of a Category 1 system as required in Section 1317.0, except as follows:

    (1) Warning systems shall be permitted to be a single alarm panel.

    (2) The alarm panel shall be located in an area of continuous surveillance while the facility is in operation.

    (3) Pressure and vacuum switches/sensors shall be mounted at the source equipment with a pressure indicator at the master alarm panel. [NFPA 99:5.2.9]

    1325.11 Category 2 Distribution. Category 2 systems shall comply with Section 1318.0 through Section 1323.12.

    [NFPA 99:5.2.10]

    1325.12 Labeling and Identification. Category 2 systems shall comply with Section 1323.13 through Section 1323.15. [NFPA 99:5.2.11]

    1325.13 Performance Criteria and Testing — Gas, Medical–Surgical Vacuum, and WAGD. Category 2 systems shall comply with Section 1324.0. [NFPA 99:5.2.12]

    2025 CALIFORNIA PLUMBING CODE 299

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    HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS

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    1326.6 Station Outlets and Inlets. Category 3 systems shall comply with Section 1315.0. [NFPA 99:5.3.5]

    1326.7 Pressure and Vacuum Indicators. Category 3 systems shall comply with Section 1316.2. [NFPA 99:5.3.8] 1326.8 Warning Systems. Warning systems associated with Category 3 systems shall provide the master, area, and local alarm functions of a Category 1 system as required in Section 1317.0, except as follows:

    (1) Warning systems shall be permitted to be a single alarm panel (i.e., a combination master/area alarm panel).

    (2) The alarm panel shall be located in an area of continuous surveillance while the facility is in operation.

    (3) Pressure and vacuum switches/sensors shall be mounted at the source equipment with a pressure indicator at the master alarm panel.

    (4) Electrical power for warning systems shall be in accordance with Section 6.6 of NFPA 99 for Category 3 and Category 4 spaces. [NFPA 99:5.3.9]

  • CPC § 1326.0 Medium relevance — show source text

    (1) Warning systems shall be permitted to be a single alarm panel.

    »

    Part IV – Category 3 Piped Gas and Vacuum Systems.

    1326.0 Category 3 Piped Gas and Vacuum Systems. 1326.1 General. Category 3 piped gas and vacuum systems shall be permitted when all of the following criteria are met:

    (1) Only minimal sedation, as defined in Chapter 2; or no sedation is performed. Deep sedation, moderate sedation, and general anesthesia are not performed.

    (2) The loss of the piped gas and vacuum systems is not likely to cause injury to patients, staff, or visitors, but can cause discomfort.

    (3) The facility piped gas and vacuum systems are intended for Category 3 patient care rooms as defined in Chapter 2. [NFPA 99:5.3.1.2]

    1326.2 Nature of Hazards of Gas and Vacuum Sys- tems. The requirement of Section 1307.2 shall apply to the nature of hazards of gas and vacuum systems. [NFPA 99:5.3.2]

    1326.3 Medical Air Supply Systems. Category 3 central supply systems shall be permitted to consist of the following:

    (1) Gas cylinder or cryogenic liquid container headers in accordance with NFPA 99.

    (2) Oxygen concentrator supply units in accordance with NFPA 99.

    (3) Cylinder manifolds for gas cylinders in accordance with NFPA 99.

    (4) Manifolds for cryogenic liquid containers in accordance with NFPA 99.

    (5) Cryogenic fluid central supply systems in accordance with NFPA 99.

    (6) Medical air compressor systems in accordance with NFPA 99.

    (7) Proportioning air systems in accordance with NFPA 99.

    (8) Medical-surgical vacuum systems in accordance with of NFPA 99.

    (9) Waste anesthetic gas disposal systems (WAGDs) in accordance with NFPA 99.

    (10)Instrument air compressor systems in accordance with NFPA 99. {NFPA 99:5.3.3.5} 1326.4 Medical–Surgical Vacuum Systems. Category 3 systems shall comply with Section 1307.3 through Section 1309.13 and Section 1312.0 through Section 1313.5, except as follows:

    (1) Medical–surgical vacuum systems shall be permitted to be simplex.

    (2) The facility staff shall develop an emergency plan to deal with the loss of medical–surgical vacuum.

    (3) Emergency electrical service shall conform to the requirements of Section 6.6 of NFPA 99 and NFPA 70.

    [NFPA 99:5.3.3.7]

    1326.5 Valves. Category 3 systems shall comply with Section 1314.0. [NFPA 99:5.3.4]

    300 2025 CALIFORNIA PLUMBING CODE

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

    HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS

    (2) The alarm panel shall be located in an area of continuous surveillance while the facility is in operation.

    (3) Pressure and vacuum switches/sensors shall be mounted at the source equipment with a pressure indicator at the master alarm panel.

  • CPC § 6402.1 Medium relevance — show source text

    SECTION 6402—DEFINITION

    6402.1 Definition. The following term is defined in Chapter 2:

    PYROPHORIC.

    SECTION 6403—GENERAL REQUIREMENTS

    6403.1 Quantities not exceeding the maximum allowable quantity per control area. The storage and use of pyrophoric materials in amounts not exceeding the maximum allowable quantity per control area indicated in Section 5003.1 shall be in accordance with Sections 5001, 5003, 6401 and 6403.

    6403.1.1 Emergency shutoff. Compressed gas systems conveying pyrophoric gases shall be provided with approved manual or automatic emergency shutoff valves that can be activated at each point of use and at each source.

    6403.1.1.1 Shutoff at source. An automatic emergency shutoff valve shall be installed on supply piping at the cylinder or bulk source. The shutoff valve shall be operated by a remotely located manually activated shutdown control located not less than 15 feet (4572 mm) from the source of supply. Manual or automatic cylinder valves are allowed to be used as the required emergency shutoff valve where the source of supply is limited to unmanifolded cylinder sources.

    6403.1.1.2 Shutoff at point of use. A manual or automatic emergency shutoff valve shall be installed on the supply piping at the point of use or at a point where the equipment using the gas is connected to the supply system.

    6403.2 Quantities exceeding the maximum allowable quantity per control area. The storage and use of pyrophoric materials in amounts exceeding the maximum allowable quantity per control area indicated in Section 5003.1 shall be in accordance with Chapter 50 and this chapter.

    SECTION 6404—STORAGE

    6404.1 Indoor storage. Indoor storage of pyrophoric materials in amounts exceeding the maximum allowable quantity per control area indicated in Table 5003.1.1(1) shall be in accordance with Sections 5001, 5003 and 5004 and this chapter.

    The storage of silane gas, and gas mixtures with a silane concentration of 1.37 percent or more by volume, shall be in accordance with ANSI/CGA G-13.

    6404.1.1 Liquid-tight floor. In addition to the requirements of Section 5004.12, floors of storage areas containing pyrophoric liquids shall be of liquid-tight construction.

    6404.1.2 Pyrophoric solids and liquids. Storage of pyrophoric solids and liquids shall be limited to a maximum area of 100 square feet (9.3 m [2] ) per pile. Storage shall not exceed 5 feet (1524 mm) in height. Individual containers shall not be stacked.

    Aisles between storage piles shall be not less than 10 feet (3048 mm) in width.

    Individual tanks or containers shall not exceed 500 gallons (1893 L) in capacity.

    6404.1.3 Pyrophoric gases. Storage of pyrophoric gases shall be in detached buildings where required by Section 5003.8.2.

    6404.1.4 Separation from incompatible materials. In addition to the requirements of Section 5003.9.8, indoor storage of pyrophoric materials shall be isolated from incompatible hazardous materials by 1-hour fire barriers with openings protected in accordance with the California Building Code.

    Exception: Storage in approved hazardous materials storage cabinets constructed in accordance with Section 5003.8.7.

  • CPC § 415.11.8.2.1 Medium relevance — show source text
    1. Except as noted in this section, monitoring for highly toxic and toxic gases shall also comply with Chapter 60 of the California Fire Code .

    [F] 415.11.8.2.1 Alarms. The gas detection system shall initiate a local alarm and transmit a signal to the emergency control station when a short-term hazard condition is detected. The alarm shall be both visual and audible and shall provide warning both inside and outside the area where the gas is detected. The audible alarm shall be distinct from all other alarms.

    [F] 415.11.8.2.2 Shutoff of gas supply. The gas detection system shall automatically close the shutoff valve at the source on gas supply piping and tubing related to the system being monitored for which gas is detected when a short-term hazard condition is detected. Automatic closure of shutoff valves shall comply with the following:

    1. Where the gas detection sampling point initiating the gas detection system alarm is within a gas cabinet or exhausted enclosure, the shutoff valve in the gas cabinet or exhausted enclosure for the specific gas detected shall automatically close.
    2. Where the gas detection sampling point initiating the gas detection system alarm is within a room and compressed gas containers are not in gas cabinets or an exhausted enclosure, the shutoff valves on all gas lines for the specific gas detected shall automatically close.

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

    SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY AND USE

    1. Where the gas detection sampling point initiating the gas detection system alarm is within a piping distribution manifold enclosure, the shutoff valve supplying the manifold for the compressed gas container of the specific gas detected shall automatically close. Exception: Where the gas detection sampling point initiating the gas detection system alarm is at the use location or within a gas valve enclosure of a branch line downstream of a piping distribution manifold, the shutoff valve for the branch line located in the piping distribution manifold enclosure shall automatically close.

    [F] 415.11.9 Manual fire alarm system. An approved manual fire alarm system shall be provided throughout buildings containing Group H-5. Activation of the alarm system shall initiate a local alarm and transmit a signal to the emergency control station. The fire alarm system shall be designed and installed in accordance with Section 907.

    [F] 415.11.10 Emergency control station. An emergency control station shall be provided in accordance with Sections 415.11.10.1 through 415.11.10.3.

    [F] 415.11.10.1 Location. The emergency control station shall be located on the premises at an approved location outside the fabrication area.

    [F] 415.11.10.2 Staffing. Trained personnel shall continuously staff the emergency control station.

    [F] 415.11.10.3 Signals. The emergency control station shall receive signals from emergency equipment and alarm and detection systems. Such emergency equipment and alarm and detection systems shall include, but not be limited to, the following where such equipment or systems are required to be provided either in this chapter or elsewhere in this code:

    1. Automatic sprinkler system alarm and monitoring systems.

    2. Manual fire alarm systems.

    3. Emergency alarm systems.

    4. Gas detection systems.

    5. Smoke detection systems.

    6. Emergency power system.

    7. Automatic detection and alarm systems for pyrophoric liquids and Class 3 water-reactive liquids required in Section 2705.2.3.4 of the California Fire Code .

  • CPC § 5802.1 Medium relevance — show source text

    SECTION 5802—DEFINITIONS

    5802.1 Definitions. The following terms are defined in Chapter 2:

    FLAMMABLE GAS.

    FLAMMABLE LIQUEFIED GAS.

    GAS DETECTION SYSTEM.

    GASEOUS HYDROGEN SYSTEM.

    HYDROGEN FUEL GAS ROOM.

    METAL HYDRIDE.

    METAL HYDRIDE STORAGE SYSTEM.

    SECTION 5803—GENERAL REQUIREMENTS

    5803.1 Quantities not exceeding the maximum allowable quantity per control area. The storage and use of flammable gases in amounts not exceeding the maximum allowable quantity per control area indicated in Section 5003.1 shall be in accordance with Sections 5001, 5003, 5801 and 5803.

    5803.1.1 Special limitations for indoor storage and use. Flammable gases shall not be stored or used in Group A, E, I or R occupancies or in offices in Group B occupancies.

    Exceptions:

    1. Cylinders of nonliquefied compressed gases not exceeding a capacity of 250 cubic feet (7.08 m [3] ) or liquefied gases not exceeding a capacity of 40 pounds (18 kg) each at normal temperature and pressure (NTP) used for maintenance purposes, patient care or operation of equipment.
    2. Food service operations in accordance with Section 6103.2.1.7.
    3. Hydrogen gas systems located in a hydrogen fuel gas room constructed in accordance with Section 421 of the Califor- nia Building Code .

    5803.1.1.1 Medical gases. Medical gas system supply cylinders shall be located in medical gas storage rooms or gas cabinets as set forth in Section 5306.

    5803.1.1.2 Aggregate quantity. The aggregate quantities of flammable gases used for maintenance purposes and operation of equipment shall not exceed the maximum allowable quantity per control area indicated in Table 5003.1.1(1).

    5803.1.2 Storage containers. Cylinders and pressure vessels for flammable gases shall be designed, constructed, installed, tested and maintained in accordance with Chapter 53.

    2025 CALIFORNIA FIRE CODE 58-3

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

    FLAMMABLE GASES AND FLAMMABLE CRYOGENIC FLUIDS

    5803.1.3 Emergency shutoff. Compressed gas systems conveying flammable gases shall be provided with approved manual or automatic emergency shutoff valves that can be activated at each point of use and at each source.

    5803.1.3.1 Shutoff at source. A manual or automatic fail-safe emergency shutoff valve shall be installed on supply piping at the cylinder or bulk source. Manual or automatic cylinder valves are allowed to be used as the required emergency shutoff valve where the source of supply is limited to unmanifolded cylinder sources.

    5803.1.3.2 Shutoff at point of use. A manual or automatic emergency shutoff valve shall be installed on the supply piping at the point of use or at a point where the equipment using the gas is connected to the supply system.

    5803.1.4 Ignition source control. Ignition sources in areas containing flammable gases in storage or in use shall be controlled in accordance with Section 5003.7.

    Exception: Fuel gas systems connected to building service utilities in accordance with the International Fuel Gas Code .

  • CPC § 6004.2.2.8 Medium relevance — show source text

    6004.2.2.8 Emergency power. Emergency power shall be provided for the following systems in accordance with Section 603:

    1. Exhaust ventilation system.

    2. Treatment system.

    3. Gas detection system.

    4. Smoke detection system.

    5. Temperature control system.

    6. Fire alarm system.

    7. Emergency alarm system.

    6004.2.2.8.1 Fail-safe engineered systems. Emergency power shall not be required for mechanical exhaust ventilation, treatment systems and temperature control systems where approved fail-safe engineered systems are installed.

    6004.2.2.9 Automatic fire detection system—highly toxic compressed gases. An approved automatic fire detection system shall be installed in rooms or areas where highly toxic compressed gases are stored or used. Activation of the detection system shall sound a local alarm. The fire detection system shall comply with Section 907.

    6004.2.2.10 Gas detection system. A gas detection system complying with Section 916 shall be provided to detect the presence of gas at or below the PEL or ceiling limit of the gas for which detection is provided. The system shall be capable of monitoring the discharge from the treatment system at or below one-half the IDLH limit and shall initiate a response in accordance with Sections 6004.2.2.10.1 through 6004.2.2.10.3 if the gas detection alarm is activated.

    Exception: A gas detection system is not required for toxic gases when the physiological warning threshold level for the gas is at a level below the accepted PEL for the gas.

    6004.2.2.10.1 Alarms. The gas detection system shall initiate a local alarm and transmit a signal to a constantly attended control station when a short-term hazard condition is detected. The alarm shall be both audible and visible and shall provide warning both inside and outside the area where gas is detected. The audible alarm shall be distinct from all other alarms.

    Exception: Signal transmission to a constantly attended control station is not required where not more than one cylinder of highly toxic or toxic gas is stored.

    6004.2.2.10.2 Shut off of gas supply. The gas-detection system shall automatically close the shutoff valve at the source on gas supply piping and tubing related to the system being monitored for whichever gas is detected.

    Exception: Automatic shutdown is not required for reactors utilized for the production of highly toxic or toxic compressed gases where such reactors are:

    1. Operated at pressures less than 15 pounds per square inch gauge (psig) (103.4 kPa).
    2. Constantly attended.
    3. Provided with emergency shutoff valves that have ready access.

    6004.2.2.10.3 Valve closure. Automatic closure of shutoff valves shall be in accordance with the following:

    1. Where the gas-detection sampling point initiating the gas detection system alarm is within a gas cabinet or exhausted enclosure, the shutoff valve in the gas cabinet or exhausted enclosure for the specific gas detected shall automatically close.
    2. Where the gas-detection sampling point initiating the gas detection system alarm is within a gas room and compressed gas containers are not in gas cabinets or exhausted enclosures, the shutoff valves on all gas lines for the specific gas detected shall automatically close.
    3. Where the gas-detection sampling point initiating the gas detection system alarm is within a piping distribution manifold enclosure, the shutoff valve for the compressed container of specific gas detected supplying the manifold shall automatically close.

Frequently asked questions

When does a dental facility need its own emergency shutoff?

If a central medical gas supply serves two treatment facilities, each facility must have its own emergency shutoff valve located in that facility and accessible from all use‑points. § 1327.2(2).

Can I use the manifold’s remote actuator as the emergency shutoff?

No. A remotely activated shutoff at a gas supply manifold shall not be used as the required emergency shutoff for clinical purposes. § 1327.2(4).

Are dental alarm panels allowed to be combined (single panel)?

Yes. Category 2 warning systems are permitted to be a single alarm panel, provided it still meets surveillance and functional requirements. § 1327.3.

At what pressure change will the alarm activate?

Alarms must indicate if main‑line pressure increases or decreases 20 percent from the normal operating pressure. § 1327.3(5).

Where must pressure sensors be installed relative to shutoff valves?

Pressure switches/sensors must be installed downstream of any emergency shutoff valves and other shutoff valves so alarms reflect the patient‑side condition. § 1327.3(7).

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