604.1 Pipe, Tube, and Fittings — 2025 California Plumbing Code

Pipe, tube, fittings, solvent cement, thread sealants, solders, and flux used in potable water systems intended to supply drinking water shall comply with NSF/ANSI/CAN 61. Where pipe fittings and valves are made from copper alloys containing more than 15 percent zinc by weight and are used in plastic piping systems, they shall be resistant to dezincification and stress corrosion cracking in compliance with NSF/ANSI 14.

Materials used in the water supply system, except valves and similar devices, shall be of a like material, except where otherwise approved by the Authority Having Jurisdiction.

Materials for building water piping and building supply piping shall comply with the applicable standards referenced in Table 604.1.

Exception: [OSHPD 1, 2, 3, 4 & 5] Use of CPVC is not per- mitted for potable water applications. 604.1.1 Local Authority to Approve CPVC Pipe Within Residential Buildings Under Specified Con- ditions. [HCD 1 & HCD 2] The local responsible build- ing official of any city, county, or city and county, shall authorize by permit the use of CPVC for hot and cold water distribution systems within the interior of residential build- ings provided all of the following conditions are satisfied:

(a) Permit Conditions. Any building permit issued pur- suant to Section 604.1.1 shall be conditioned on compliance with the mitigation measures set forth in this section.

(b) Approved Materials. Only CPVC plumbing mate- rial listed as an approved material and installed in accordance with this code may be used.

(c) Installation and Use. Any installation and use of CPVC plumbing material pursuant to this section shall comply with all applicable requirements of this code and the manufacturer’s installation instructions.

(d) Certification of Compliance. Prior to issuing a building permit pursuant to Section 604.1.1, the building official shall require as part of the permit- ting process that the contractor, or the appropriate plumbing subcontractors, provide written certifica- tion: (1) that is required in subdivision (e), and (2) that he or she will comply with the flushing proce- dures and worker safety measures of this code and the manufacturer’s installation instructions.

(e) Worker Safety. Any contractor applying for a build- ing permit that includes the use of CPVC plumbing materials authorized pursuant to this section shall include in the permit application a signed written certification stating that:

(1) They are aware of the health and safety hazards associated with CPVC plumbing installations;

(2) They have included in their Injury and Illness Prevention Plan the hazards associated with CPVC plumbing pipe installations; and

(3) The worker safety training elements of their Injury and Illness Prevention Plan meet the Department of Industrial Relation’s guidelines.

(f) Findings of Compliance. The building official shall not give final permit approval of any CPVC plumbing materials installed pursuant to Section 604.1.1 unless he or she finds that the material has been installed in compliance with the requirements of this code and the manufacturer’s installation instructions.

(g) Penalties. Any contractor or subcontractor found to have failed to comply with the flushing, ventilation, and glove requirements of this code and the manu- facturer’s installation instructions shall be subject to the penalties in Health and Safety Code, Division 13, Part 1.5, Chapter 6 (Section 17995 et seq.). In addition, if during the conduct of any building inspection the building official finds that the venti- lation and glove requirements of this code, are being violated, such building officials shall cite the con- tractor or subcontractor for that violation.

(h) Special Requirements for CPVC Installation within Residential Structures. In addition to the other requirements in the California Plumbing Code, all installations of CPVC pipe within resi- dential structures shall meet the following:

(i) Flushing Procedures. All installations of CPVC pipe within residential structures shall be flushed twice over a period of at least one (1) week. The pipe system shall be first flushed for at least 10 minutes and then filled and allowed to stand for no less than 1 week, after which all the branches of the pipe system must be flushed long enough to fully empty the con- tained volume. At the time of the fill, each fix- ture shall have a removable tag applied stating:

“This new plumbing system was first filled on (date) by (name). The California Department of Housing and Community Development requires that the sys- tem be flushed after standing at least one week after the fill date specified above. If the system is used ear- lier than one week after the fill date, the water must be allowed to run for at least two minutes prior to use for human consumption. This tag may not be removed prior to flushing, except by the homeowner.”

(ii) Worker Safety Measures. Mechanical ventila- tion sufficient to maintain exposures below the relevant exposure limits established by state regulation shall be provided in enclosed spaces. This ventilation shall be directed at the breath- ing zone of the worker installing the pipe. Where mechanical ventilation is not practical, respirators, suitable for organic vapors, shall be used. For the purpose of this subdivision, an enclosed space is defined as:

(1) A space less than 100 square feet of floor area under a ceiling with a height of 10 feet or less, and which does not have openings (consisting of doors, windows, or unfin- ished walls) on at least two sides;

(2) Crawl spaces having a height of less than three feet;

(3) Enclosed attics that have a roof and ceil- ing; or

(4) Trenches having a depth greater than 24 inches.

Installers of CPVC pipe within residential struc- tures shall use non-latex thin gauge (4 millime- ters) nitrile gloves, or other gloves providing an equivalent or better degree of protection during the installation of the CPVC plumbing system. Gloves shall be provided to all workers by the contractor, or plumbing subcontractor, and shall be replaced upon contamination by cements.

604.1.2 PEX. [HCD 1 & HCD 2] All installations of PEX pipe where it is the initial plumbing piping installed in new construction shall be flushed twice over a period of at least one week. The pipe system shall be first flushed for at least 10 minutes and then filled and allowed to stand for no less than 1 week, after which all the branches of the pipe system must be flushed long enough to fully empty the contained volume. This provision shall not apply to the installation of PEX pipe where it replaces an existing pipe system of any material.

(1) At the time of fill, each fixture shall have a remov- able tag applied stating:

(a) “This new plumbing system was first filled and _flushed on ______ (date) by ____________ (name). The State of California requires that the system be flushed after standing at least one week after the fill date specified above. If this system is used earlier than one week after the fill date, the water must be allowed to run for at least two minutes prior to use for human con- sumption. This tag may not be removed prior to the completion of the required second flushing, except by the building owner or occupant.”

(2) Prior to issuing a building permit to install PEX pipe, the building official shall require as part of the permitting process that the contractor, or the appro- priate plumbing subcontractors, provide written cer- tification that he or she will comply with the flushing procedures set forth in the code.

(3) The building official shall not give final permit approval of any PEX plumbing installation unless he or she finds that the material has been installed in compliance with the requirements of the code, includ- ing the requirements to flush and tag the systems.

(4) Any contractor or subcontractor found to have failed to comply with the PEX flushing requirements shall be subject to the penalties in Health and Safety Code, Division 13, Part 1.5, Chapter 6 (Section 17995, et seq.).