CPC · California Plumbing Code

Alarms, pressure/vacuum indicators and emergency shutoff valve requirements

Q: Can a dental clinic use a remotely actuated manifold valve as the emergency shutoff?

No. A remotely activated shutoff valve at a gas supply manifold shall not be used for emergency shutoff ; the code requires an accessible emergency shutoff per facility. § 1327.2(4) .

Q: Where must the alarm panel be located for Category 3 systems?

A single alarm panel (permitted for Category 3) must be located in an area of continuous surveillance while the facility is in operation . § 1326.8(2) .

Q: At what pressure must the piping be tested?

Initial pressure test = 1.5 × system operating pressure but not less than 150 psi (and tests must be done before installing components that would be damaged by test pressure). § 1327.4.3 and § 1324.5.1 .

For homeowners: the CPC requires readable pressure gauges where alarms are initiated, alarms that warn when pipeline pressure changes by ±20%, and emergency shutoffs that are labeled and reachable from every use point; dental clinics must have a manual shutoff per facility and test piping to 1.5× operating pressure (but at least 150 psi) before installing pressure‑sensitive components.

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Last reviewed: July 6, 2026

What the code requires — in plain English

The California Plumbing Code requires that medical gas and vacuum systems have readable pressure/vacuum indicators, properly located warning systems (alarms) and emergency shutoff valves sized and located so they are accessible in an emergency. Key controls are in § 1326.7, § 1326.8, and § 1327.2 and the CPC ties these requirements to the NFPA 99 performance rules referenced in those sections. See § 1326.7 and § 1326.8 for Category 3 system alarm and indicator rules and § 1327.2 for dental (Category 2) emergency shutoff valve rules.

Emergency shutoff valves must be accessible from all use-point locations in an emergency, and pressure switches/sensors must be installed downstream of shutoff valves so alarms reflect downstream conditions.

Requirements in detail

Defined terms (first appearance bolded)

Warning system — the alarm system for medical gas/vacuum (master/area/local functions) as required by the CPC/NFPA provisions. § 1326.8, § 1325.10, § 1317.0.
Pressure/vacuum indicator — a readable gauge or indicator required at specific locations (see locations). § 1326.7, § 1316.2.
Emergency shutoff valve — a manually accessible valve that isolates supply to a treatment facility/area in an emergency. § 1327.2.

Short decision table — what to install where

Decision dimension	Required value / action	Code reference
Alarm scope for Category 3 systems	May use a single (combined master/area) alarm panel; alarm panel must be in an area of continuous surveillance while facility operates	§ 1326.8(1–2)
Alarm functions & thresholds (medical gas)	Alarms for main-line pressure low, main-line pressure high, and changeover (oxygen/nitrous oxide); visual non-cancelable indication if main-line pressure changes ±20% from normal operating pressure; visual must remain until resolved; audible indications per § 1317.0	§ 1326.8(4–6) and § 1317.1(2–3,8)
Pressure/vacuum indicator locations	Indicators readable from a standing position and provided at: (1) adjacent to alarm-initiating device for source main line pressure/vacuum alarms; (2) at/area alarm panels; (3) on station outlet/inlet side of zone valves	§ 1326.7 referencing § 1316.2
Placement of pressure switches/sensors	Install downstream of any emergency shutoff valves and any other shutoff valves so alarms reflect downstream pressure; must alarm if pressure changes ±20%	§ 1326.8(7)
Emergency shutoff valve — accessibility	Accessible from all use‑point locations in the emergency area/facility; where one central supply serves two treatment facilities, provide a shutoff for each facility accessible from all use points	§ 1327.2(1–2)
Emergency shutoff valve — labeling & scope	Valves must be labeled to indicate the gas controlled and must shut off only the gas to the treatment facility they serve	§ 1327.2(3)
Remote actuators for shutoff	Remotely activated shutoff valve at manifold shall not be used for emergency shutoff; remote actuators must not fail‑close on loss of electric power for clinical purposes; if they fail‑open, cylinder valves must be closed when system not in use	§ 1327.2(4)
Initial pressure test (positive-pressure gases)	Test each piping section after blowdown, after rough-in, and prior to installing components that would be damaged (e.g., indicators, alarm devices). Test pressure = 1.5 × system operating pressure but not less than 150 psi; maintain pressure while inspecting for leaks (use oil-free dry nitrogen NF; oxygen-safe leak detectant)	§ 1327.4, § 1327.4.1, § 1327.4.3 and § 1324.5 / § 1324.5.1

(See code references column for the official sections.)

Notes about alarm performance

Category 1 (full master/area/local) alarm performance (visuals remain latched until corrected, cancelable audible with reinitiation on new alarm, minimum 80 dBA at 3 ft for audible, etc.) is specified in § 1317.1 and is applied (with exceptions) to Category 2 and 3 systems as noted in § 1325.10 and § 1326.8.

Exceptions & special cases

Category 3 systems are explicitly permitted to use a single combined alarm panel (master/area), rather than separate panels — provided the panel is in continuous surveillance while the facility operates. § 1326.8(1–2).
Pressure/vacuum indicators must be readable from a standing position and are required at specific monitoring points (master alarm device, area panel, and on the station outlet/inlet side of zone valves). § 1316.2 / § 1326.7.
Some components (plastic vacuum piping, scavenging plastic piping) are excluded from pressure testing; check § 1327.4 and related testing rules before installing pressure-sensitive components. § 1327.4.
Remote manifold‑actuated valves are specifically not acceptable as the emergency shutoff for clinical emergencies; the code requires an accessible manual shutoff within each treatment facility (and adds operational constraints on remote actuators). § 1327.2(4).

Common mistakes

Installing pressure switches/sensors upstream of an emergency shutoff valve so the alarm reads the wrong side of the valve — the CPC requires sensors downstream of shutoffs so they reflect usable pressure. § 1326.8(7).
Assuming a remote‑actuated manifold valve counts as an emergency shutoff — the CPC prohibits using a remotely activated manifold shutoff for emergency shutoff purposes. § 1327.2(4).
Omitting readable pressure indicators at the required locations (master alarm, area panel, station outlet side of zone valves). Indicators must be readable from a standing position. § 1316.2 / § 1326.7.
Failing to test piping at the required pressure: initial test pressure is 1.5× operating pressure but not less than 150 psi, and testing must occur before installing pressure‑sensitive components. § 1327.4 / § 1324.5.1.

Worked example — dental operatory oxygen system (numbers applied)

Scenario: A dental operatory has a Category 2 oxygen piping system with a nominal operating pressure of 50 psi (example pressure used in CPC examples for outlet adapters). The designer must satisfy alarms, indicators, shutoffs and testing.

Emergency shutoff valve: provide a manual emergency shutoff accessible from all use‑point locations in that treatment facility (so the dentist or assistant can reach it during an emergency). The valve must be labeled for oxygen and must only shut off gas to that facility. § 1327.2(1,3).
Alarm thresholds: install pressure switches/sensors downstream of the emergency shutoff valve so alarms reflect the usable pipeline pressure. Program the alarm to trip if pressure rises or falls ±20% of the normal operating pressure. For a nominal 50 psi operating pressure that means visual (noncancelable) alarm at ≤ 40 psi and ≥ 60 psi. § 1326.8(5–7).
Indicator locations: provide a pressure indicator readable from standing position at the master/area panel and at the station outlet/inlet side of the zone valve for the operatory. § 1316.2 / § 1326.7.
Initial pressure test: before installing pressure‑sensitive alarm devices/indicators, perform the initial pressure test. Required test pressure = 1.5 × operating pressure = 75 psi — but the code requires the test pressure not be less than 150 psi, so the installer must test at 150 psi and hold while inspecting for leaks with oxygen‑safe detectant. § 1327.4.3 and § 1324.5.1.

Related provisions (quick links)

§ 1316.2 — Pressure/vacuum indicator locations (readable from standing position; locations list).
§ 1317.0 / § 1317.1 — Warning system performance (visual latch, audible level, reinitiate rules).
§ 1324.5 / § 1324.5.1 — Initial pressure testing requirements and required test pressure (1.5× operating pressure; not less than 150 psi).
§ 1314.10 — Zone valves, location and indicators (readily accessible outside the area controlled).
§ 1327.4 — Dental system initial pressure testing and provisions about components not to be present during test.

Code references

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

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 § 1325.13 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]

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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]

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 § 1315.14 High relevance — show source text
(1) They shall be gas-specific.

(2) They shall be pressure-specific where a single gas is piped at more than one operating pressure [e.g., a station outlet for oxygen at 80 psi (552 kPa) shall not accept an adapter for oxygen at 50 psi (345 kPa)].

(3) If operated at a pressure in excess of 80 psi (552 kPa), they shall be either D.I.S.S. connectors or comply with Section 1315.14(4).

(4) If operated at a gauge pressure between 200 psi and 300 psi (1379 kPa and 2068 kPa), the station outlet shall be designed so as to prevent the removal of the adapter until the pressure has been relieved to prevent the adapter injuring the user or others when removed from the outlet. [NFPA 99:5.1.5.15]

1315.15 Post Installation. After installation of the piping, but before installation of the station outlets and inlets and other medical gas and medical gas system components (e.g., pressure-actuating switches for alarms, manifolds, pressure gauges, or pressure relief valves), the line shall be blown clear using oil-free, dry nitrogen NF.

1316.0 Pressure and Vacuum Indicator Locations.

1316.1 Isolation. A pressure-relief valve shall not be isolated from its intended use by a valve.

1316.2 Pressure and Vacuum Indicator Locations.

Pressure/vacuum indicators shall be readable from a standing position. Pressure/vacuum indicators shall be provided at the following locations, as a minimum:

(1) Adjacent to the alarm-initiating device for source main line pressure and vacuum alarms in the master alarm sys tem.

(2) At or in area alarm panels to indicate the pressure/vacuum at the alarm activating device for each system that is monitored by the panel.

(3) On the station outlet/inlet side of zone valves. [NFPA 99:5.1.8.2.1, 5.1.8.2.2]

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HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS

1317.0 Warning Systems. 1317.1 Category 1. All master, area, and local alarm systems used for medical gas and vacuum systems shall include the following:

(1) Separate visual indicators for each condition monitored, except as permitted in Section 1317.1.2 for local alarms that are displayed on master alarm panels.

(2) Visual indicators that remain in alarm until the situation that has caused the alarm is resolved.

(3) Cancelable audible indication of each alarm condition that produces a sound with a minimum level of 80 dBA at 3 feet (914 mm).

(4) Means to indicate a lamp or LED failure and audible fail ure.

(5) Visual and audible indication that the communication with an alarm-initiating device is disconnected.

(6) Labeling of each indicator, indicating the condition monitored.

(7) Labeling of each alarm panel for its area of surveillance.

(8) Reinitiating of the audible signal if another alarm condition occurs while the audible alarm is silenced.

(9) Power for master alarms, area alarms, sensors, and switches from the life safety branch of the essential electrical system as described in NFPA 99.
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

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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 § 1325.7 High 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 § 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.

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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 § 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]

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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 § 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]

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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 § 1307.0 Medium relevance — show source text
Notes: 1 Includes pediatric nursery. 2 Includes obstetric recovery. 3 Emergency trauma rooms used for surgical procedures shall be classified as general operating rooms. 4 Vacuum inlets required are in addition to inlets used as part of a scavenging system for removal of anesthetizing gases.

Part II – Category 1 Piped Gas and Vacuum Systems.

1307.0 Central Supply Systems.

1307.1 Terms. Where the terms medical gas or medical support gas occur, the provisions shall apply to all piped systems for oxygen, nitrous oxide, medical air, carbon dioxide, helium, nitrogen, instrument air, and mixtures thereof. Wherever the name of a specific gas service occurs, the provision shall apply only to that gas. [NFPA 99:5.1.1.3] 1307.2 Nature of Hazards of Gas and Vacuum Sys- tems. Potential fire and explosion hazards associated with positive pressure gas central piping systems and medical–surgical vacuum systems shall be considered in the design, installation, testing, operation, and maintenance of these systems. [NFPA 99:5.1.2]

1307.3 Permitted Locations for Medical Gases. Central supply systems for oxygen, medical air, nitrous oxide, carbon dioxide, and all other patient medical gases shall be piped only to medical gas outlets complying with Section 1315.0, into areas where the gases will be used under the direction of licensed medical professionals for purposes congruent with the following:

(1) Direct respiration by patients.

(2) Clinical application of the gas to a patient, such as the use of an insufflator to inject carbon dioxide into patient body cavities during laparoscopic surgery and carbon dioxide used to purge heart-lung machine blood flow

ways.

(3) Medical device applications directly related to respiration.

(4) Power for medical devices used directly on patients.

(5) Calibration of medical devices intended for Section 1307.3(1) through Section 1307.3(4).

(6) Simulation centers for the education, training, and assessment of health care professionals. [NFPA 99:5.1.3.5.2]

1307.4 Materials. Materials used in central supply systems shall meet the following requirements:

(1) In those portions of systems intended to handle oxygen at gauge pressures greater than 350 pounds-force per square inch (psi) (2413 kPa), interconnecting hose shall contain no polymeric materials.

(2) In those portions of systems intended to handle oxygen or nitrous oxide material, construction shall be compatible with oxygen under the temperatures and pressures to which the components can be exposed in the containment and use of oxygen, nitrous oxide, mixtures of these gases, or mixtures containing more than 23.5 percent oxygen.

(3) If potentially exposed to cryogenic temperatures, materials shall be designed for low temperature service.

(4) If intended for outdoor installation, materials shall be installed per the manufacturer’s requirements. [NFPA 99:5.1.3.5.4]

1308.0 Pressure-Regulating Equipment.

1308.1 Where Required. Pressure-regulating equipment shall be installed in the supply main upstream of the final linepressure valve. Where multiple piping systems for the same gas at different operating pressures are required, separate pressure-regulating equipment, relief valves, and source shutoff valves shall be provided for each pressure.

1308.2 Pressure Relief Valves. All pressure relief valves shall meet the following requirements:
CPC § 5.9.1.1 Medium relevance — show source text
Gas and air combustion mixers incorporating double diaphragm “zero” or “atmosphere” governors or regulators shall require no further protection unless connected directly to compressed air or oxygen at pressures of 5 psi (34 kPa) or more. [NFPA 54:5.9.1.1 – 5.9.1.2]

1208.11.1 Protective Devices. Protective devices

shall include but not be limited to the following:

(1) Check valves.

(2) Three-way valves (of the type that completely closes one side before starting to open the other side).

(3) Reverse flow indicators controlling positive shutoff valves.

(4) Normally closed air-actuated positive shutoff pressure regulators. [NFPA 54:5.9.2]

1208.12 Low-Pressure Protection. A protective device shall be installed between the meter and the appliance or equipment if the operation of the appliance or equipment is such that it could produce a vacuum or a dangerous reduction in gas pressure at the meter. Such protective devices include, but are not limited to, mechanical, diaphragm-operated, or electrically operated low-pressure shutoff valves. [NFPA 54:5.10]

1208.13 Shutoff Valves. Shutoff valves shall be selected in

accordance with Table 1208.13. Shutoff valves of size 1 inch

(25 mm) National Pipe Thread and smaller shall be listed and labeled. Where used outdoors, such use shall be in accordance with the manufacturer’s recommendation. [NFPA 54:5.11]

1208.14 Expansion and Flexibility. Piping systems shall be designed to prevent failure from thermal expansion or contraction. [NFPA 54:5.13.1]

1208.14.1 Special Local Conditions. Where local conditions include earthquake, tornado, unstable ground, or flood hazards, special consideration shall be given to increased strength and flexibility of piping supports and connections. [NFPA 54:5.13.2]

1208.15 Pressure Regulator and Pressure Control Venting. The venting of the atmospheric side of diaphragms in line pressure regulators, gas appliance regulators, and gas pressure limit controls shall be in accordance with all of the following:

(1) An independent vent pipe to the outdoors, sized in accordance with the device manufacturer’s instructions, shall be provided where the location of a device is such that a discharge of fuel gas will cause a hazard. For devices other than appliance regulators, vents are not required to be independent where the vents are connected to a common manifold designed in accordance with engineering methods to minimize backpressure in the event of diaphragm failure and such design is approved.

Exceptions:

(1) A regulator and vent limiting means combination listed as complying with CSA/ANSI Z21.80/CSA 6.22, shall not be required to be vented to the outdoors.

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FUEL GAS PIPING

(2) A listed gas appliance regulator factory equipped with a vent limiting device is not required to be vented to the outdoors.

(2) Materials for vent piping shall be in accordance with Section 1208.5 through Section 1208.5.12.5.
CPC § 1324.0 Medium relevance — show source text
1324.0 Performance Criteria and Testing Category 1 (Gases, Medical Surgical Vacuum). 1324.1 Where Required. Inspection and testing shall be performed on components, or portions thereof, of new, piped medical gas or vacuum systems, additions, renovations, temporary installations, or repaired systems in accordance with Section 1324.2 through Section 1324.5.11, and certified in accordance with Section 1306.0.

1324.2 Breached Systems. All systems that are breached and components that are subject to additions, renovations, or replacement (e.g., new gas sources: bulk, manifolds, compressors, dryers, alarms) shall be inspected and tested. Systems shall be deemed breached at the point of pipeline intrusion by physical separation or by system component removal, replacement, or addition. Breached portions of the systems subject to inspection and testing shall be confined to only the specific altered zone and components in the immediate zone or area that is located upstream for vacuum systems and downstream for pressure gases at the point or area of intrusion. [NFPA 99:5.1.12.1.3 – 5.1.12.1.5]

1324.2.1 Reports. The inspection and testing reports shall be submitted directly to the party that contracted for the testing, who shall submit the report through channels to the responsible facility authority and any others that are required. Reports shall contain detailed listings of all findings and results. [NFPA 99:5.1.12.1.6, 5.1.12.1.7] 1324.3 Test Gas. The test gas shall be oil-free, dry nitrogen NF. [NFPA 99:5.1.12.2.1.2]

1324.4 Initial Piping Blowdown. Piping in medical gas and vacuum distribution systems shall be blown clear by means of oil-free, dry nitrogen NF after installation of the distribution piping but before installation of station outlet/inlet rough-in assemblies and other system components (e.g., pressure/vacuum alarm devices, pressure/vacuum indicators, pressure relief valves, manifolds, source equipment). [NFPA 99:5.1.12.2.2]

1324.5 Initial Pressure Tests – Medical Gas and Vac- uum Systems. Each section of the piping in medical gas and vacuum systems shall be pressure tested. 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, line pressure relief valves). [NFPA 99:5.1.12.2.3.1, 5.1.12.2.3.2]

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HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS

1324.5.1 Shutoff Valve. The source shutoff valve shall

remain closed during tests specified in Section 1324.5 through Section 1324.5.1.2. [NFPA 99:5.1.12.2.3.3]
CPC § 5.1.4.6.1 Medium relevance — show source text
(2) It is readily operable from a standing position.

(3) It is installed where it is visible and accessible at all times.

(4) It is not installed where it can be hidden from plain view, such as behind normally open or normally closed doors.

(5) It is not installed in a room with the station outlets/inlets that it controls.

(6) It is not installed in rooms, areas, or closets that can be closed or locked. [NFPA 99:5.1.4.6.1]

1314.10.1 Readily Accessible. A zone valve in each medical gas or vacuum line shall be provided for each Category 1 space and anesthetizing location for moderate sedation, deep sedation, or general anesthesia specific for the occupancy, and shall be located as follows:

(1) They are installed immediately outside the area controlled.

(2) They are installed where they are visible and accessible at all times. [NFPA 99:5.1.4.6.2]

1314.10.2 Arrangement. Piping on the patient side of zone valves shall be arranged to provide the following:

(1) Shutting off the supply of medical gas or vacuum to one zone will not affect the supply of medical gas or vacuum to another zone or the rest of the system.

(2) Service will only be to outlets/inlets located on that same story.

(3) All gas delivery columns, hose reels, ceiling tracks, control panels, pendants, booms, or other special installations are located on the patient side of the zone valve. [NFPA 99:5.1.4.6.3]

TABLE 1314.5(1) POSITIVE PRESSURE GASES

[NFPA 99: TABLE 5.1.4.1.6(a)]

For SI units: 1 inch = 25.4 mm

TABLE 1314.5(2) VACUUM AND WAGD

[NFPA 99:TABLE 5.1.4.1.6(b)]

For SI units: 1 inch = 25.4 mm

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HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS

1314.10.3 Indicators. A pressure/vacuum indicator shall be provided on the station outlet/inlet side of each zone valve. [NFPA 99:5.1.4.6.4]

1314.11 In-Line Shutoff Valves. Optional in-line valves shall be permitted to be installed to isolate or shut off piping for servicing of individual rooms or areas. [NFPA 99:5.1.4.7]

1314.12 Valves for Future Connections. Future con nection valves shall be labeled as to gas content. [NFPA 99:5.1.4.8.1]

1314.12.1 Downstream Piping. Downstream piping shall be closed with a brazed cap with tubing allowance for cutting and rebrazing. [NFPA 99:5.1.4.8.2]

1315.0 Station Outlets and Inlets.

Frequently asked questions

Must pressure switches always be downstream of emergency shutoff valves?

Yes. The CPC states pressure switches/sensors shall be installed downstream of any emergency shutoff valves and any other shutoff valves so the alarm reflects usable pressure. § 1326.8(7).

Can a dental clinic use a remotely actuated manifold valve as the emergency shutoff?

No. A remotely activated shutoff valve at a gas supply manifold shall not be used for emergency shutoff; the code requires an accessible emergency shutoff per facility. § 1327.2(4).

What triggers the main-line pressure alarm?

For medical gas alarms the CPC requires that audible and noncancelable visual alarms indicate if main-line pressure increases or decreases 20 percent from normal operating pressure. § 1326.8(5).

Where must the alarm panel be located for Category 3 systems?

A single alarm panel (permitted for Category 3) must be located in an area of continuous surveillance while the facility is in operation. § 1326.8(2).

At what pressure must the piping be tested?

Initial pressure test = 1.5 × system operating pressure but not less than 150 psi (and tests must be done before installing components that would be damaged by test pressure). § 1327.4.3 and § 1324.5.1.

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Related in the CPC

Blowdown, purging, initial pressure tests and leak testing for new or altered systems

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California Plumbing Code