CMC · California Mechanical Code
What are the pressure test requirements and minimum test hold times?
For a homeowner: before your process piping system is approved, the inspector will witness a pressure test. If a liquid (hydraulic) test is used the system must be held at one‑and‑one‑half times its design pressure; if a gas (pneumatic) test is used it must be held at 110% of design pressure. The pressure must not visibly fall during the minimum 30‑minute hold — the inspector may require a longer test.
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
The California Mechanical Code requires a final pressure test of installed process piping. The piping must stand a pressure of not less than one‑and‑one‑half times the maximum designed operating pressure when hydraulic testing is used, or 110 percent when pneumatic testing is used, and the test pressure must be held for a time satisfactory to the Authority Having Jurisdiction but not less than 30 minutes with no perceptible drop. This requirement is stated in § 1405.2.2.
The piping must be tested at 1.5× design pressure for hydro tests or 110% for pneumatic tests, and held at that pressure at least 30 minutes without a perceptible drop — in the presence of the inspector (Authority Having Jurisdiction).
Requirements in detail
Key defined terms (bolded on first mention): hydraulic testing, pneumatic testing, Authority Having Jurisdiction. The controlling provision is § 1405.2.2.
Basic numeric requirements
| Decision item | Required value / action | Code Reference |
|---|---|---|
| Hydraulic test pressure | 1.5 × maximum designed operating pressure | § 1405.2.2 |
| Pneumatic test pressure | 110% (1.10 ×) of maximum designed operating pressure | § 1405.2.2 |
| Minimum hold time | Not less than 30 minutes (or a longer time if required by the AHJ) | § 1405.2.2 |
| Acceptable leakage during test | No perceptible drop in pressure while held | § 1405.2.2 |
| Presence of inspector | Tests shall be made in the presence of the Authority Having Jurisdiction | § 1405.2.2 |
| Apparatus | Necessary test apparatus must be furnished by the permit holder | § 1405.2.2 |
| HPM drain/waste/vent piping | Tested in accordance with the plumbing code (not this section) | § 1405.2.2 |
Notes:
- The code gives the AHJ discretion to require a longer hold time than the 30‑minute minimum. Always confirm with the inspector before testing.
- The section applies to the final piping inspection after piping is installed and concealed portions are in place.
What the code does not specify (and where to look)
- Test medium: § 1405.2.2 does not prescribe the test medium (water, air, inert gas). For system‑specific test mediums and additional rules, other CMC sections apply (for example, refrigeration systems require dry nitrogen for pressure tests in § 1116.3).
- Special systems: Some systems have separate, more detailed testing procedures and longer hold times (e.g., closed‑loop ground heat exchanger testing in § 1710.6.2).
Exceptions & special cases
- Authority Having Jurisdiction (AHJ) may require a longer hold time or different test protocol — the 30‑minute period is a minimum floor, not necessarily the final requirement. § 1405.2.2 gives the AHJ that discretion.
- HPM drain, waste, and vent piping are not covered by this section and must be tested per the Plumbing Code (referenced in § 1405.2.2).
- Systems with separate CMC chapters: for example, closed‑loop geothermal loops have specific procedures and hold times (maximum test pressure = 1.5× design, not over 100 psi; long hold and monitoring sequence) in § 1710.6.2. Follow that section instead of the chapter‑14 generic rule for those systems.
- Refrigeration and refrigerant‑containing systems have their own test medium and limitations (e.g., § 1116.3 specifies dry nitrogen or inert nonflammable gases and pressure‑build protection). Use the relevant CMC chapter for such systems.
Common mistakes
- Using the wrong multiplier: applying 1.5× (hydro) when conducting a pneumatic test — pneumatic tests require 110% per § 1405.2.2.
- Holding the test for less than 30 minutes or not confirming AHJ’s required hold time — the code’s minimum is 30 minutes but the AHJ can require more.
- Not performing the test in the presence of the AHJ or not notifying the inspector when the system is ready for final inspection. § 1405.2.2 requires tests to be made in the presence of the AHJ.
- Failing to isolate or remove equipment that can be damaged by test pressure (the code expects appliances/devices that cannot withstand the test to be disconnected or blinded — confirm with AHJ and other applicable sections).
- Using inappropriate test media for specialty systems — e.g., oxygen for pressure tests is prohibited in other code chapters; refrigeration testing has specific gas allowances in § 1116.3. Always check the specific chapter before choosing the medium.
Worked example — concrete scenario
Scenario: Process piping with a maximum designed operating pressure of 100 psi.
If you perform a hydraulic (liquid) test: required test pressure = 1.5 × 100 psi = 150 psi. Apply 150 psi, hold for at least 30 minutes with no perceptible drop, in the presence of the AHJ. Document the test and provide the apparatus. § 1405.2.2.
If you perform a pneumatic (gas) test: required test pressure = 110% × 100 psi = 110 psi. Apply 110 psi, hold for at least 30 minutes with no perceptible drop, in the presence of the AHJ. § 1405.2.2.
Important cautions in either case:
- If any adjacent equipment or components cannot tolerate the test pressure, isolate or remove them before pressurizing. Confirm with AHJ. § 1405.2.2.
- For some systems (e.g., ground loops) different procedures apply — see § 1710.6.2 for longer multi‑stage tests and monitoring requirements.
Related provisions (CMC sections)
- § 1405.2.1 — Rough piping inspection (timing of inspections relative to final pressure test).
- § 1405.2.2 — Final piping inspection; pressure test requirements and minimum hold time (controlling section).
- § 1710.6.2 — U‑bends and headers, closed‑loop geothermal: test pressure limits and a 4‑hour hold + 1‑hour monitoring sequence (system‑specific procedure and acceptance).
- § 1710.6.2.1 / 1710.6.2.2 — Test pressure limits (1.5× design, not to exceed 100 psi) and the detailed testing procedure for ground loops.
- § 1116.3 — Refrigeration test gas requirements and pressure‑build protection for refrigeration systems (test media and restrictions).
- § 1117.3 — Pneumatic and hydrostatic test multipliers for small pressure vessels in the refrigeration chapter (shows how multipliers are used in other CMC contexts).
(If you need a direct printout of the cited code text for the inspector or permit file, I can extract the exact wording from the code files cited above.)
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 8.1.3.5 High relevance — show source text
** Where the piping system is connected to appliances or equipment designed
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FUEL GAS PIPING
for operating pressures equal to or greater than the test pressure, such appliances or equipment shall be isolated from the piping system by closing the individual appliance or equipment shutoff valve(s). [NFPA 54:8.1.3.5]
1213.2.6 Safety. All testing of piping systems shall be performed in a manner that protects the safety of employees and the public during the test. [NFPA 54:8.1.3.6]
1213.3 Test Pressure. This inspection shall include an air, CO 2, or nitrogen pressure test, at which time the gas piping shall stand a pressure of not less than 10 psi (69 kPa) gauge pressure. Test pressures shall be held for a length of time satisfactory to the Authority Having Jurisdiction but in no case less than 15 minutes with no perceptible drop in pressure. For welded piping, and for piping carrying gas at pressures in excess of 14 inches water column pressure (3.5 kPa), the test pressure shall be not less than 60 psi (414 kPa) and shall be continued for a length of time satisfactory to the Authority Having Jurisdiction, but in no case for less than 30 minutes. For CSST carrying gas at pressures in excess of 14 inches water column (3.5 kPa) pressure, the test pressure shall be not less than 30 psi (207 kPa) for 30 minutes. These tests shall be made using air, CO 2, or nitrogen pressure and shall be made in the presence of the Authority Having Jurisdiction. Necessary apparatus for conducting tests shall be furnished by the permit holder. Test gauges used in conducting tests shall be in accordance with Section 318.0.
1213.4 Detection of Leaks and Defects. The piping system shall withstand the test pressure specified without showing any evidence of leakage or other defects. Any reduction of test pressures as indicated by pressure gauges shall be deemed to indicate the presence of a leak unless such reduction can be readily attributed to some other cause. [NFPA 54:8.1.5.1]
1213.4.1 Detecting Leaks. The leakage shall be located by means of an approved gas detector, a noncorrosive leak detection fluid, or other approved leak detection methods. [NFPA 54:8.1.5.2]
1213.4.2 Repair or Replace. Where leakage or other defects are located, the affected portion of the piping system shall be repaired or replaced and retested. [NFPA 54:8.1.5.3]
1213.5 Piping System Leak Test. Leak checks using fuel gas shall be permitted in piping systems that have been pressure-tested in accordance with Section 1213.0 through Section 1213.4.2. [NFPA 54:8.2.1]
1213.5.1 Turning Gas On. During the process of turning gas on into a system of new gas piping, the entire system shall be inspected to determine that there are no open fittings or ends and that all valves at unused outlets are closed and plugged or capped. [NFPA 54:8.2.2]
CMC § 1405.2 High relevance — show source text
Excavations required for the installation of underground piping shall be kept open until such time as the piping has been inspected and approved. Where such piping is covered or concealed before such approval, it shall be exposed upon the direction of the Authority Having Jurisdiction.
1405.2 Required Inspections. The Authority Having Jurisdiction shall make the following inspections and shall either approve that portion of the work as completed or shall notify the permit holder wherein the same fails to be in accordance with this code.
1405.2.1 Rough Piping Inspection. This inspection shall be made after process piping authorized by the permit has been installed and before piping has been cov
ered or concealed. This inspection shall include a determination that the piping size, material, and installation are in accordance with the requirements of this code.
1405.2.2 Final Piping Inspection. This inspection shall be made after piping authorized by the permit has been installed and after portions thereof that are to be covered or concealed are so concealed. This inspection shall include a pressure test, at which time the piping shall stand a pressure of not less than one-and-one-half times the maximum designed operating pressure where hydraulic testing is conducted or 110 percent where testing is conducted pneumatically. Test pressures shall be held for a length of time satisfactory to the Authority Having Jurisdiction, but in no case for less than 30 minutes with no perceptible drop in pressure. HPM drain, waste, and vent piping shall be tested in accordance with the plumbing code. Tests shall be made in the presence of the Authority Having Jurisdiction. Necessary apparatus for conducting tests shall be furnished by the permit holder.
1405.3 Other Inspections. In addition to the inspections required by this section, the Authority Having Jurisdiction shall be permitted to require a special inspector, as specified in the building code, during installation of piping systems. In cases where the work authorized was installed in accordance with plans and specifications prepared by a registered design professional, the Authority Having Jurisdiction shall be permitted to require a final signed report stating that the work was installed in accordance with approved plans and specifications and the applicable provisions of this chapter.
1406.0 Pipe, Tubing, and Fittings.
1406.1 General. Process pipe, tubing, and fittings shall comply with ASME B31.3 and shall be installed in accordance with the manufacturer’s installation instructions. Materials shall be rated for the operating temperatures and pressures of the system, and shall be compatible with the type of liquid.
1406.2 Hazardous Process Piping (HPP). HPP supply piping or tubing in service corridors shall be exposed to view. HPP piping shall be identified in accordance with nationally recognized standards to indicate the material being transported. Liquid HPP piping shall have an approved means for directing spilled materials to an approved containment or drainage system.
Liquid HPP waste or drainage systems shall be installed in accordance with the plumbing code.
1406.2.1 Installation in Exit Corridors and Above Other Occupancies. Hazardous process supply pipe shall not be located within exit corridors, within a portion of a means of egress required to be enclosed in fire-resistive construction, or in concealed spaces in or above
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areas not classified as Group H Occupancies, except as permitted by this subsection.
CMC § 1401.0 High relevance — show source text
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CHAPTER 14
PROCESS PIPING
1401.0 General.
1401.1 Applicability. Except as otherwise addressed in this code, this chapter shall govern the installation of process piping in or in conjunction with a building or structure located upon the premises.
1402.0 Permit.
1402.1 General. It shall be unlawful to install, alter, or repair or cause to be installed, altered, or repaired process material piping without first obtaining a permit.
Permits for process piping shall show the total number of outlets to be provided for on each system and such other information as required by the Authority Having Jurisdiction.
Fees for process piping permits are included in Table 104.5.
1403.0 Plans Required.
1403.1 General. Plans, engineering calculations, diagrams, and other data shall be submitted in one or more sets with each application for a permit. The Authority Having Jurisdiction shall be permitted to require plans, computations, and specifications to be prepared and designed by a registered design professional.
Where plans or other data are submitted for review, a plan review fee shall be paid, as provided in Section 104.3.2.
1404.0 Workmanship.
1404.1 General. Process piping shall not be strained or bent, nor shall tanks, vessels, vats, appliances, or cabinets be supported by or develop strain or stress on the piping.
1405.0 Inspections.
1405.1 General. Upon completion of the installation, alteration, or repair of process piping, and prior to the use thereof, the Authority Having Jurisdiction shall be notified that such piping is ready for inspection.
Excavations required for the installation of underground piping shall be kept open until such time as the piping has been inspected and approved. Where such piping is covered or concealed before such approval, it shall be exposed upon the direction of the Authority Having Jurisdiction.
1405.2 Required Inspections. The Authority Having Jurisdiction shall make the following inspections and shall either approve that portion of the work as completed or shall notify the permit holder wherein the same fails to be in accordance with this code.
1405.2.1 Rough Piping Inspection. This inspection shall be made after process piping authorized by the permit has been installed and before piping has been cov
ered or concealed. This inspection shall include a determination that the piping size, material, and installation are in accordance with the requirements of this code.
1405.2.2 Final Piping Inspection. This inspection shall be made after piping authorized by the permit has been installed and after portions thereof that are to be covered or concealed are so concealed. This inspection shall include a pressure test, at which time the piping shall stand a pressure of not less than one-and-one-half times the maximum designed operating pressure where hydraulic testing is conducted or 110 percent where testing is conducted pneumatically. Test pressures shall be held for a length of time satisfactory to the Authority Having Jurisdiction, but in no case for less than 30 minutes with no perceptible drop in pressure. HPM drain, waste, and vent piping shall be tested in accordance with the plumbing code. Tests shall be made in the presence of the Authority Having Jurisdiction. Necessary apparatus for conducting tests shall be furnished by the permit holder.
CMC § 8.1.1.6 High relevance — show source text
[NFPA 54:8.1.1.6] 1213.1.6 Test Medium. The test medium shall be air, nitrogen, carbon dioxide, or an inert gas. Oxygen shall not be used as a test medium. [NFPA 54:8.1.2] 1213.2 Test Preparation. Test preparation shall comply with Section 1213.2.1 through Section 1213.2.6. 1213.2.1 Pipe Joints. Pipe joints, including welds, shall be left exposed for examination during the test. Exception: Covered or concealed pipe end joints that have been previously tested in accordance with this code.
[NFPA 54:8.1.3.1] 1213.2.2 Expansion Joints. Expansion joints shall be provided with temporary restraints, if required, for the additional thrust load under test. [NFPA 54:8.1.3.2] 1213.2.3 Appliances and Equipment. Appliances and equipment that are not to be included in the test shall be either disconnected from the piping or isolated by blanks, blind flanges, or caps. Flanged joints at which blinds are inserted to blank off other equipment during the test shall not be required to be tested. [NFPA 54:8.1.3.3] 1213.2.4 Designed for Operating Pressures Less Than Test Pressure. Where the piping system is connected to appliances or equipment designed for operating pressures of less than the test pressure, such appliances or equipment shall be isolated from the piping system by disconnecting them and capping the outlet(s). [NFPA 54:8.1.3.4] 1213.2.5 Designed for Operating Pressures Equal to or Greater Than Test Pressure. Where the piping system is connected to appliances or equipment designed
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for operating pressures equal to or greater than the test pressure, such appliances or equipment shall be isolated from the piping system by closing the individual appliance or equipment shutoff valve(s). [NFPA 54:8.1.3.5]
1213.2.6 Safety. All testing of piping systems shall be performed in a manner that protects the safety of employees and the public during the test. [NFPA 54:8.1.3.6]
1213.3 Test Pressure. This inspection shall include an air, CO 2, or nitrogen pressure test, at which time the gas piping shall stand a pressure of not less than 10 psi (69 kPa) gauge pressure. Test pressures shall be held for a length of time satisfactory to the Authority Having Jurisdiction but in no case less than 15 minutes with no perceptible drop in pressure. For welded piping, and for piping carrying gas at pressures in excess of 14 inches water column pressure (3.5 kPa), the test pressure shall be not less than 60 psi (414 kPa) and shall be continued for a length of time satisfactory to the Authority Having Jurisdiction, but in no case for less than 30 minutes. For CSST carrying gas at pressures in excess of 14 inches water column (3.5 kPa) pressure, the test pressure shall be not less than 30 psi (207 kPa) for 30 minutes.
CMC § 1710.6.1 High relevance — show source text
1710.6.1 Backfill. Bentonite grout and thermallyenhanced bentonite grout, where used to seal and backfill each borehole, shall comply with NSF/ANSI/CAN 60. Boreholes shall be backfilled in accordance with the Authority Having Jurisdiction.
1710.6.2 U-Bends and Headers. Headers, u-bends and ground loop pipes shall be pressure-tested in accordance with ANSI/ CSA/IGSHPA C448, or as required by the Authority Having Jurisdiction. Before testing, heat fusion joints shall be cooled to ambient temperature. Mechanical joints shall be completely assembled. Flushing and purging to remove air and debris shall be completed before testing. The assembly shall be filled with water (or water/antifreeze solution) and purged at a minimum flow rate of 2 feet per second (0.6 m/s) to remove air, but not more than the maximum flow velocity recommended by the pipe and fittings manufacturer to remove debris.
1710.6.2.1 Test Pressure. The maximum test pressure shall be 1.5 times the system design pressure, as determined by Section 1710.6.2.3, or Section 1710.6.2.4, not to exceed 100 psi (689 kPa). Components or devices with lower pressure-ratings than the pipe shall be protected from excessive pressure during testing by removing or isolating from the test section.
Exception: Where lower pressure-rated components or devices cannot be removed or isolated from the test section, the maximum test pressure shall not exceed the pressure rating of the component or device.
1710.6.2.2 Testing Procedure. The test section and the test liquid shall be at the same temperature. The test section shall be filled with liquid and purged of air. The test section shall be brought to the specified test pressure. Test pressure shall be maintained for 4 hours, with additional fluid added as needed. The test pressure shall be reduced by 10 psi (69 kPa) and monitored for 1 hour with no addition of pres
sure or additional fluid. A passing test is indicated where after a period of 1 hour no visual leakage is observed, and pressure remains equal to or greater than 95 percent of the original pressure.
1710.6.2.3 Calculation of Static Pressure (Water). For water, the static pressure applied shall be equivalent to 0.43 psig (2.96 kPa) per foot (305 mm) of elevation.
1710.6.2.4 Calculation of Static Pressure (Other Fluids). For fluids of different density, the static pressure shall be calculated using the density of the system fluid.
1711.0 Ground-Heat Exchanger Testing.
1711.1 Testing. Pressure-testing of the ground-heat exchanger shall be performed in accordance with the testing method in Section 1710.6.
1711.2 Individual Loop Pressure Testing. Individual loop testing shall be performed as required by the Authority Having Jurisdiction.
1711.3 Field Pressure Testing – Final. The ground-heat exchanger and building piping shall be cleaned, flushed, and, where required, shall be filled with the heat transfer fluid medium. The ground loop system shall be tested at the design flow rate(s) and differential pressure(s) recorded. Where the actual pressure change at design flow is more than +/- 10 percent of the design flow pressure drop, the cause shall be identified, and corrective action taken.
CMC § 1116.3 High relevance — show source text
(2) Refrigeration systems containing Group R-22, not exceeding 5 tons of refrigeration capacity (18 kW), and field-piped using approved, factory-charged line sets shall be permitted to be proved tight by observing retention of pressure on a set of charging gauges and soaping connections while the system is operating.
1116.3 Test Gases. Tests shall be performed with dry nitrogen or another nonflammable, nonreactive, dried gas. Oxygen, air, or mixtures containing them shall not be used. The means used to build up the test pressure shall have either a pressure limiting device or a pressure reducing device and a gauge on the outlet side. The pressure relief device shall be set above the test pressure but low enough to prevent permanent deformation of the system’s components.
Exceptions:
(1) Mixtures of dry nitrogen, inert gases, or a combination thereof such with Class 1 refrigerants in concentrations of a refrigerant weight fraction (mass fraction) not exceeding 5 percent shall be permitted for tests.
(2) Mixtures of dry nitrogen, inert gases, or a combination thereof such with Class 2L, Class 2, and Class 3 refrigerants in concentrations not exceeding the lesser of a refrigerant weight fraction (mass fraction) of 5 percent or 25 percent of the LFL shall be permitted for tests.
(3) Compressed air without added refrigerant shall be permitted for tests, provided the system is subsequently evacuated to less than 1000 microns (0.1333 kPa) before charging with refrigerant. The required evacuation level is atmospheric pressure for systems using R718 (water) or R-744 (carbon dioxide) as the refrigerant.
(4) Systems erected on the premises using Group A1 refrigerant and with copper tubing not exceeding 0.62 of an inch (15.7 mm) outside diameter shall be tested by means of the refrigerant charged into the system at the saturated vapor pressure of the refrigerant at not less than 68°F (20°C). [ASHRAE 15:10.1.2]
1116.4 Declaration. A dated declaration of test shall be
provided for systems containing more than 55 pounds (24.9 kg) of refrigerant. The declaration shall give the name of the refrigerant and the field test pressure applied to the highside and the lowside of the system. The declaration of test shall be signed by the installer and, where an inspector is present at the tests, the inspector shall also sign the declaration. Where requested, copies of this declaration shall be furnished to the Authority Having Jurisdiction. [ASHRAE 15:10.2]
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REFRIGERATION
1116.5 Brine Systems. Brine-containing portions of a system shall be tested at one and a half times the design pressure of the system using brine as the test fluid.
1117.0 Refrigerant-Containing Pressure Vessels.
1117.1 Inside Dimensions 6 Inches or Less. Pressure vessels having inside dimensions of 6 inches (152 mm) or less shall be:
(1) Listed either individually or as part of an assembly by an approved, nationally recognized testing laboratory, or
CMC § 1901.3.4.3.2 High relevance — show source text
2. Rebar dowels. When adhesive anchor systems are used to install reinforcing dowel bars in hardened concrete, 25 percent of dowels shall be tested if all the following conditions are met: 2.1. The dowels are used exclusively to transmit shear forces across joints between existing and new concrete. 2.2. The number of dowels in any one member equals or exceeds twelve (12). 2.3. The dowels are uniformly distributed across seismic force resisting members (such as shear walls, collec- tors and diaphragms).
1901.3.4.3.2 Nonstructural applications. Fifty percent of post-installed anchors used in nonstructural applications shall be proof tested. The percentage of tested anchors applies to each set of anchors of a common type (e.g., adhesive, wedge, or shell and sleeve for expansion bolts), size, and embedment depth and to each group of anchors. Four or more anchors connected to a common element shall be defined as a group.
Exceptions: 1. Repetitive anchors. When anchors are used repetitively (with three or more identical anchors) in distribution systems (such as pipe, duct or conduit supports) or architectural systems (such as suspended ceilings, cladding, and partitions), 20 percent of anchors, including at least one anchor in each group, shall be tested. 2. Anchors with low tension. When the design tension on anchors is less than 100 pounds and those anchors are clearly noted on the approved construction documents, 10 percent of anchors shall be tested.
1901.3.4.4 Test loads. [OSHPD 1R, 2 & 5] Required test loads shall be determined by one of the following methods: 1. Twice the maximum allowable tension load or one and a quarter (1 [1] / 4 ) times the maximum design strength of anchors as provided in approved evaluation report using criteria adopted in this code or determined in accordance with Chapter 17 of ACI 318.
Tension test load need not exceed 80 percent of the nominal yield strength of the anchor element (= 0.8 A se f ya ). 2. The manufacturer’s recommended installation torque based on approved evaluation report using criteria adopted in this code.
1901.3.4.5 Test acceptance criteria. [OSHPD 1R, 2 & 5] Proof test shall satisfy the following minimum requirements. 1. Tension test: Anchors shall be tested in the unconfined condition in accordance with ASTM E3121 except that the mini- mum clearance to the test frame shall be 1.5 times the anchor’s embedment depth. Test load shall be maintained for a
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CONCRETE
minimum of 15 seconds and shall exhibit no discernable movement during the tension test, e.g. as evidenced by loosen- ing of the washer under the nut or an abrupt decrease in the gauge pressure. Exception: Adhesive anchors shall be permitted to be tested in confined conditions in accordance with ASTM E3121 when the approved construction documents indicate that concrete breakout does not control the design tensile strength. _2.
CMC § 1710.4 High relevance — show source text
1710.4 Underground Fittings. Underground fittings for closed-loop systems shall be in accordance with Section 1703.3 and Table 1703.3.
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GEOTHERMAL ENERGY SYSTEMS AND AMBIENT TEMPERATURE LOOPS
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1710.5 Verification. For closed-loop systems, the system shall be flushed of debris and purged of air after completion of the entire ground-heat exchanger. Flow rates and pressure drops shall be compared to calculated values to assure no blockage or kinking of the pipe. A report shall be submitted to the owner to confirm that the loop flow is in accordance with the construction documents.
1710.6 Vertical Bores. Vertical bores shall be drilled to a depth to provide complete insertion of the u-bend pipe to its specified depth. The borehole diameter shall be sized for the installation and placement of the heat exchange u-bend and the tremie used to place the grouting material. ANSI/ CSA/IGSHPA C448 shall be used for vertical loop depth and borehole diameter sizing guidance. The u-bend joint and pipe shall be visually inspected for integrity in accordance with the manufacturer’s installation instructions. The u-bend joint and pipe shall be pressurized to not less than 100 psi (689 kPa), not to exceed the pressure rating of the pipe at the test temperature, for 1 hour to check for leaks before insertion into the borehole.
1710.6.1 Backfill. Bentonite grout and thermallyenhanced bentonite grout, where used to seal and backfill each borehole, shall comply with NSF/ANSI/CAN 60. Boreholes shall be backfilled in accordance with the Authority Having Jurisdiction.
1710.6.2 U-Bends and Headers. Headers, u-bends and ground loop pipes shall be pressure-tested in accordance with ANSI/ CSA/IGSHPA C448, or as required by the Authority Having Jurisdiction. Before testing, heat fusion joints shall be cooled to ambient temperature. Mechanical joints shall be completely assembled. Flushing and purging to remove air and debris shall be completed before testing. The assembly shall be filled with water (or water/antifreeze solution) and purged at a minimum flow rate of 2 feet per second (0.6 m/s) to remove air, but not more than the maximum flow velocity recommended by the pipe and fittings manufacturer to remove debris.
1710.6.2.1 Test Pressure. The maximum test pressure shall be 1.5 times the system design pressure, as determined by Section 1710.6.2.3, or Section 1710.6.2.4, not to exceed 100 psi (689 kPa). Components or devices with lower pressure-ratings than the pipe shall be protected from excessive pressure during testing by removing or isolating from the test section.
Exception: Where lower pressure-rated components or devices cannot be removed or isolated from the test section, the maximum test pressure shall not exceed the pressure rating of the component or device.
CMC § 0.62 Medium relevance — show source text
(4) Systems erected on the premises using Group A1 refrigerant and with copper tubing not exceeding 0.62 of an inch (15.7 mm) outside diameter shall be tested by means of the refrigerant charged into the system at the saturated vapor pressure of the refrigerant at not less than 68°F (20°C). [ASHRAE 15:10.1.2]
1116.4 Declaration. A dated declaration of test shall be
provided for systems containing more than 55 pounds (24.9 kg) of refrigerant. The declaration shall give the name of the refrigerant and the field test pressure applied to the highside and the lowside of the system. The declaration of test shall be signed by the installer and, where an inspector is present at the tests, the inspector shall also sign the declaration. Where requested, copies of this declaration shall be furnished to the Authority Having Jurisdiction. [ASHRAE 15:10.2]
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REFRIGERATION
1116.5 Brine Systems. Brine-containing portions of a system shall be tested at one and a half times the design pressure of the system using brine as the test fluid.
1117.0 Refrigerant-Containing Pressure Vessels.
1117.1 Inside Dimensions 6 Inches or Less. Pressure vessels having inside dimensions of 6 inches (152 mm) or less shall be:
(1) Listed either individually or as part of an assembly by an approved, nationally recognized testing laboratory, or
(2) Marked directly on the vessel or on a nameplate attached to the vessel with a “U” or “UM” symbol signifying compliance with ASME BPVC Section VIII.1, or
(3) When requested by the Authority Having Jurisdiction, the manufacturer shall provide documentation to confirm that the vessel meets the design, fabrication, and testing requirements of ASME BPVC Section VIII.1.
Exception: Vessels having an internal or external design pressure of 15 psig (103 kPag) or less.
Pressure vessels having inside dimensions of 6 inches (152 mm) or less shall be protected by either a pressure-relief device or a fusible plug. [ASHRAE 15:9.3.1.1]
1117.1.1 Pressure-Relief Device. Where a pressurerelief device is used to protect a pressure vessel having an inside dimension of 6 inches (152 mm) or less, the ultimate strength of the pressure vessel so protected shall withstand a pressure of not less than 3.0 times the design pressure. [ASHRAE 15:9.3.1.2]
1117.1.2 Fusible Plug. Where a fusible plug is used to protect a pressure vessel having an inside diameter of 6 inches (152 mm) or less, the ultimate strength of the pressure vessel so protected shall withstand a pressure 2.5 times the saturation pressure of the refrigerant used at the temperature stamped on the fusible plug or 2.5 times the critical pressure of the refrigerant used, whichever is less.
[ASHRAE 15:9.3.1.3]
CMC § 9.3.1.1 Medium relevance — show source text
(1) Listed either individually or as part of an assembly by an approved, nationally recognized testing laboratory, or
(2) Marked directly on the vessel or on a nameplate attached to the vessel with a “U” or “UM” symbol signifying compliance with ASME BPVC Section VIII.1, or
(3) When requested by the Authority Having Jurisdiction, the manufacturer shall provide documentation to confirm that the vessel meets the design, fabrication, and testing requirements of ASME BPVC Section VIII.1.
Exception: Vessels having an internal or external design pressure of 15 psig (103 kPag) or less.
Pressure vessels having inside dimensions of 6 inches (152 mm) or less shall be protected by either a pressure-relief device or a fusible plug. [ASHRAE 15:9.3.1.1]
1117.1.1 Pressure-Relief Device. Where a pressurerelief device is used to protect a pressure vessel having an inside dimension of 6 inches (152 mm) or less, the ultimate strength of the pressure vessel so protected shall withstand a pressure of not less than 3.0 times the design pressure. [ASHRAE 15:9.3.1.2]
1117.1.2 Fusible Plug. Where a fusible plug is used to protect a pressure vessel having an inside diameter of 6 inches (152 mm) or less, the ultimate strength of the pressure vessel so protected shall withstand a pressure 2.5 times the saturation pressure of the refrigerant used at the temperature stamped on the fusible plug or 2.5 times the critical pressure of the refrigerant used, whichever is less.
[ASHRAE 15:9.3.1.3]
1117.2 Inside Dimensions More than 6 Inches. Pressure vessels having an inside diameter exceeding 6 inches (152 mm) and having an internal or external design pressure greater than 15 psig (103 kPag) shall be directly marked, or marked on a nameplate, with a “U” or “UM” symbol signifying compliance with the rules of ASME BPVC Section VIII.1. [ASHRAE 15:9.3.2]
1117.3 Pressure Vessels for 15 psig or Less. Pressure vessels having an internal or external design pressure of 15 psig (103 kPag) or less shall have an ultimate strength to withstand not less than 3.0 times the design pressure and shall be tested with a pneumatic test pressure of not less than 1.25 times the design pressure or a hydrostatic test pressure of not less than 1.5 times the design pressure. [ASHRAE 15:9.3.3]
1118.0 Maintenance and Operation.
1118.1 General. Refrigeration systems shall be operated and maintained as required by the fire code.
Part II – Cooling Towers.
1119.0 General.
1119.1 Applicability. Cooling towers, evaporative condensers, fluid coolers, and associated remote sump tanks shall be readily accessible. Where located on roofs, such equipment having combustible exterior surfaces shall be protected with an approved automatic fire-extinguishing system.
1120.0 Support and Anchorage.
CMC § 0.8 Medium relevance — show source text
Tension test load need not exceed 80 percent of the nominal yield strength of the anchor element (= 0.8 A se f ya ). 2. The manufacturer’s recommended installation torque based on approved evaluation report using criteria adopted in this code.
1901.3.4.5 Test acceptance criteria. [OSHPD 1R, 2 & 5] Proof test shall satisfy the following minimum requirements. 1. Tension test: Anchors shall be tested in the unconfined condition in accordance with ASTM E3121 except that the mini- mum clearance to the test frame shall be 1.5 times the anchor’s embedment depth. Test load shall be maintained for a
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CONCRETE
minimum of 15 seconds and shall exhibit no discernable movement during the tension test, e.g. as evidenced by loosen- ing of the washer under the nut or an abrupt decrease in the gauge pressure. Exception: Adhesive anchors shall be permitted to be tested in confined conditions in accordance with ASTM E3121 when the approved construction documents indicate that concrete breakout does not control the design tensile strength. 2. Torque test: Torque-controlled post-installed anchors tested with a calibrated torque wrench shall attain the specified torque within [1] / 2 turn of the nut; or one-quarter ( [ 1] / 4 ) turn of the nut for a [3] / 8 -inch sleeve anchor only. Screw-type anchors tested with a calibrated torque wrench shall attain the specified torque within one-quarter ( [ 1] / 4 ) turn of the screw after initial seating of the screw head.
1901.4 Composite structural steel and concrete structures. Systems of structural steel acting compositely with reinforced concrete shall be designed in accordance with Section 2206 of this code.
1901.5 Construction documents. The construction documents for structural concrete construction shall include:
The specified compressive strength of concrete at the stated ages or stages of construction for which each concrete element is designed.
The specified strength or grade of reinforcement.
The size and location of structural elements, reinforcement and anchors.
Provision for dimensional changes resulting from creep, shrinkage and temperature.
The magnitude and location of prestressing forces.
Anchorage length of reinforcement and location and length of lap splices.
Type and location of mechanical and welded splices of reinforcement.
Details and location of contraction or isolation joints specified for plain concrete.
Minimum concrete compressive strength at time of posttensioning.
Stressing sequence for posttensioning tendons.
For structures assigned to Seismic Design Category D, E or F, a statement if slab on grade is designed as a structural diaphragm.
1901.6 Special inspections and tests. S pecial inspections and tests of concrete elements of buildings and structures and concreting operations shall be as required by Chapter 17.
1901.7 Tolerances for structural concrete. Where not indicated in construction documents, structural tolerances for concrete structural elements shall be in accordance with this section.
CMC § 3.2 Medium relevance — show source text
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SPECIAL INSPECTIONS AND TESTS
considered to have successfully met the test requirements if the assembly recovers not less than 75 percent of the maximum deflection within 24 hours after the removal of the test load. The test assembly shall then be reloaded and subjected to an increasing superimposed load until either structural failure occurs or the superimposed load is equal to two and one-half times the load at which the deflection limitations specified in Section 1709 A .3.2 were reached, or the load is equal to two and one-half times the superimposed design load. In the case of structural components and assemblies for which deflection limitations are not specified in Section 1709 A .3.2, the test specimen shall be subjected to an increasing superimposed load until structural failure occurs or the load is equal to two and one-half times the desired superimposed design load. The allowable superimposed design load shall be taken as the least of:
- The load at the deflection limitation given in Section 1709 A .3.2.
- The failure load divided by 2.5.
- The maximum load applied divided by 2.5.
1709 A .3.2 Deflection. The deflection of structural members under the design load shall not exceed the limitations in Section 1604 A .3.
1709 A .4 Wall and partition assemblies. Load-bearing wall and partition assemblies shall sustain the test load both with and without window framing. The test load shall include all design load components. Wall and partition assemblies shall be tested both with and without door and window framing.
1709 A .5 Exterior window and door assemblies. The design pressure rating of exterior windows and doors in buildings shall be determined in accordance with Section 1709 A .5.1 or 1709 A .5.2. For exterior windows and doors tested in accordance with Section 1709 A .5.1 or 1709 A .5.2, required design wind pressures determined from ASCE 7 shall be permitted to be converted to allowable stress design by multiplying by 0.6.
Exception: Structural wind load design pressures for window or door assemblies other than the size tested in accordance with Section 1709 A .5.1 or 1709 A .5.2 shall be permitted to be different than the design value of the tested assembly, provided that such pressures are determined by accepted engineering analysis or validated by an additional test of the window or door assembly to the alternative allowable design pressure in accordance with Section 1709 A .5.2. Components of the alternate size assembly shall be the same as the tested or labeled assembly. Where engineering analysis is used, it shall be performed in accordance with the analysis procedures of AAMA 2502 or WDMA I.S. 11.
Frequently asked questions
Can I use air for the pressure test called out in § 1405.2.2?
Section § 1405.2.2 does not prescribe a specific test medium; it prescribes pressure multipliers and hold time. For system‑specific limitations on test media (for example refrigeration), see the applicable CMC chapter such as § 1116.3.
What if the pressure drops slightly during the 30‑minute hold?
The code requires no perceptible drop during the minimum hold period per § 1405.2.2. Any measurable reduction is presumed to indicate leakage unless attributable to another identifiable cause; repair and retest as required by the AHJ.
Who must witness the test?
Tests must be made in the presence of the Authority Having Jurisdiction (the inspector). Notify the AHJ so the final piping inspection and test can be performed with the inspector present per § 1405.2.2.
Is 30 minutes always enough?
No — 30 minutes is the statutory minimum in § 1405.2.2, but the AHJ may require a longer hold time depending on system, hazard, or local practice. Confirm with the inspector.
Are there different procedures for geothermal ground loops?
Yes — closed‑loop ground‑heat exchanger testing has a more detailed procedure, a 4‑hour pressurization followed by a 1‑hour monitored reduction check, and a maximum test pressure limit (see § 1710.6.2 and related subsections). Use that section for ground‑loop acceptance.
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