CPC · California Plumbing Code

How must nonpotable piping and components be identified?

Q: How often do I need to repeat the label on a long run of pipe?

Labels must be visible from floor level and repeated every 20 ft (6096 mm) or not less than once per room , per § 601.3.2.

Q: What size letters do I use for small 1" OD tubing?

Follow Table 601.3.2 : for 1/2"–1-1/4" OD , use a minimum color field length of 8 inches and minimum letter size of 1/2 inch . See § 601.3.2.

For homeowners: nonpotable water pipes must be clearly labeled so they’re never used for drinking. The code requires yellow bands and “CAUTION: NONPOTABLE WATER, DO NOT DRINK” for general nonpotable lines and purple bands with source‑specific wording for gray/reclaimed/rainwater systems; labels must be readable from the floor, repeated every 20 feet or at least once per room, and use the minimum letter sizes shown in the CPC table.

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Last reviewed: July 6, 2026

What the code requires — 2–4 sentences

Nonpotable water systems must be clearly identified by color, wording, and periodic markings so they are not confused with potable supplies. For alternate water sources (gray, reclaimed/recycled, on‑site treated, rainwater) the CPC requires a purple background and specified wording under § 601.3.3, and general nonpotable systems use yellow markings with prescribed text and letter sizes under § 601.3.2. These identification marks must show the liquid conveyed and the direction of normal flow, and be visible from floor level at the required spacing.

The single most important rule: mark nonpotable piping with the required background color and the words (e.g., “CAUTION: NONPOTABLE WATER, DO NOT DRINK.”) and repeat the marking at the specified intervals so anyone can identify it at a glance.

Requirements in detail

Colors and basic wording

Nonpotable water (general) — yellow background with black uppercase lettering, using the words “CAUTION: NONPOTABLE WATER, DO NOT DRINK.” The system must also show the liquid being conveyed and direction of normal flow. § 601.3.2 (see source).
Alternate water sources (exceptions to yellow) — purple background (Pantone No. 512, 522C or equivalent) with uppercase lettering; wording differs by source:
- Gray water — “CAUTION: NONPOTABLE GRAY WATER, DO NOT DRINK.”
- Reclaimed (recycled) water (outdoor) — “CAUTION: NONPOTABLE RECLAIMED (RECYCLED) WATER, DO NOT DRINK.”
- On‑site treated — “CAUTION: ON‑SITE TREATED NONPOTABLE WATER, DO NOT DRINK.”
- Rainwater catchment — “CAUTION: NONPOTABLE RAINWATER, DO NOT DRINK.”
  These are required by § 601.3.3.

Marking frequency and visibility

Markings must be located so they are visible from floor level and must be repeated every 20 feet (6096 mm) along the piping run but not less than once per room. See § 601.3.2.

Outlets and fixtures

Each outlet on a nonpotable water line used for special purposes must be posted with the black uppercase wording: “CAUTION: NONPOTABLE WATER, DO NOT DRINK.” See § 601.3.5. (Note: identification of the discharge side of vacuum breakers/backflow devices serving Chapter 17 fixtures may be omitted per § 601.3.4.)

Rainwater catchment systems (CPC Chapter 16)

Rainwater catchment systems specifically are required to have color and marking information in accordance with Chapter 16 and to use the wording “CAUTION: NONPOTABLE RAINWATER, DO NOT DRINK” in the lettering style required by § 601.3.3; see § 1602.8.
Outside hose bibbs that supply rainwater must be marked “CAUTION: NONPOTABLE RAINWATER, DO NOT DRINK” and displayed per Figure 1603.2 (see § 1603.2).

Component identification

System components (e.g., tanks, pumps, listed fittings) shall be properly identified as to the manufacturer and, where applicable, marked per the system color/label requirements (see Chapter 16 general requirements and § 1601.4).

Nonpotable piping where corrective actions impractical

If a domestic line is reclassified as nonpotable because cross‑connections cannot practically be corrected, exposed portions must be identified to the satisfaction of the Authority Having Jurisdiction; outlets that are permitted for drinking/domestic use must be posted “CAUTION: NONPOTABLE WATER, DO NOT DRINK.” See § 603.5.11.

Decision‑relevant dimensions & lettering (summary table)

Decision item	Key value / threshold	Where to find it
Marking spacing	Every 20 ft (6096 mm) or not less than once per room	§ 601.3.2
Alternate source background color	Purple (Pantone No. 512, 522C or equivalent)	§ 601.3.3
Standard nonpotable background color	Yellow with black uppercase lettering	§ 601.3.2
Required wording (general)	“CAUTION: NONPOTABLE WATER, DO NOT DRINK.” (or source‑specific wording in § 601.3.3)	§ 601.3.2 and § 601.3.3
Minimum letter size and length of color field (by outside pipe OD)	See table — e.g., 1/2"–1-1/4" OD: 8" color field, 1/2" letters; >10" OD: 32" field, 3-1/2" letters	Table 601.3.2 (in § 601.3.2)
Rainwater wording requirement	“CAUTION: NONPOTABLE RAINWATER, DO NOT DRINK.”	§ 1602.8

(See Table 601.3.2 in the CPC for the complete set of diameter-to-letter size requirements.)

Exceptions & special cases

Alternate water source systems (gray, reclaimed/recycled/outdoor, on‑site treated, rainwater) use purple markings and source‑specific wording instead of the general yellow marking rule — § 601.3.3.
Recycled/reclaimed water systems that are located completely inside a building may be subject to different provisions (see the DWR exception referencing Section 1505.7 in § 601.3.3).
Where identification is impractical on concealed piping, the Authority Having Jurisdiction may require exposed portions or other identification measures in locations satisfactory to them (see § 603.5.11).

Important note about requested section: I could not locate the text of § 1603.11 in the files provided. Because the developer requested grounding each controlling section in retrieved text, I will not infer or invent requirements attributed to § 1603.11. If you need content specifically from § 1603.11, please upload or point me to that section or I can re-run a targeted search if you want. (The other required sections — § 601.3.3 and § 1602.8 — are present in the retrieved files.)

Common mistakes

Failing to use the purple background and source‑specific wording for alternate water sources (mixing purple and yellow rules). § 601.3.3 clarifies the alternate‑source exception.
Using incorrect letter size or an insufficient color field length for the pipe outside diameter — check Table 601.3.2 for minimum letter sizes and color field lengths.
Placing markings too far apart or only at equipment rooms — markings must be visible from floor level and every 20 ft (6096 mm) or at least once per room. § 601.3.2.
Forgetting to post warning wording at each outlet used for special purposes (required by § 601.3.5).

Worked example — concrete scenario

Scenario: An indoor rainwater loop (3-inch outside diameter) supplies trap primers and a nonpotable water outlet inside a maintenance room.

Apply the code:

Because this is a rainwater catchment system, use the purple background and the exact wording “CAUTION: NONPOTABLE RAINWATER, DO NOT DRINK.” per § 601.3.3 and § 1602.8.
For a 3‑inch OD pipe, Table 601.3.2 requires (for 2-1/2 to 6 in. OD) a minimum color field length of 12 inches and minimum letter size of 1-1/4 inches. Apply a purple wrap/paint band at least 12" long and letter the required caution text in ≥1-1/4" uppercase black letters. § 601.3.2.
Place those markings so they are visible from floor level, and repeat every 20 ft along the run and at least once in the maintenance room. § 601.3.2.
At each outlet used for special purposes in the room, post “CAUTION: NONPOTABLE RAINWATER, DO NOT DRINK.” in black uppercase lettering (per § 601.3.5 and Chapter 16 marking rules).

Related provisions

§ 601.3.2 — Color, information, frequency, and Table 601.3.2 (letter sizes / color field lengths).
§ 601.3.3 — Alternate water sources (purple background and source‑specific wording).
§ 601.3.5 — Posting required at nonpotable outlets.
§ 603.5.11 — Nonpotable water piping identification when lines are reclassified due to cross‑connections.
§ 1602.8 — Rainwater catchment system color and marking information (uses § 601.3.3 wording).
§ 1603.2 — Outside hose bibb marking for rainwater systems (Figure 1603.2 reference).

Code references

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

CPC § 601.3.3 High relevance — show source text

Except as required by Section 601.3.3, nonpotable water systems shall have a yellow background with black uppercase lettering, with the words “CAUTION: NONPOTABLE WATER, DO NOT DRINK.” Each nonpotable system shall be identified to designate the liquid being conveyed, and the direction of normal flow shall be clearly shown. The minimum size of the letters and length of the color field shall comply with Table 601.3.2.

[HCD 1 & HCD 2] An international symbol of a glass in a circle with a slash through it shall be provided sim- ilar to that shown in Figure 601 for all nonpotable water

systems.

2025 CALIFORNIA PLUMBING CODE 137

WATER SUPPLY AND DISTRIBUTION

FIGURE 601

INTERNATIONAL SYMBOL

The background color and required information shall be indicated every 20 feet (6096 mm) but not less than once per room, and shall be visible from the floor level.

601.3.3 Alternate Water Sources. Alternate water source systems shall have a purple (Pantone color No. 512, 522C, or equivalent) background with uppercase lettering and shall be field or factory marked as follows:

(1) Gray water systems shall be marked in accordance with this section with the words “CAUTION: NONPOTABLE GRAY WATER, DO NOT DRINK” in black letters.

(2) Reclaimed (recycled) water systems for outdoor applications shall be marked in accordance with this section with the words: “CAUTION: NONPOTABLE RECLAIMED (RECYCLED) WATER, DO NOT DRINK” in black letters.

(3) On-site treated water systems shall be marked in accordance with this section with the words: “CAU TION: ON-SITE TREATED NONPOTABLE WATER, DO NOT DRINK” in black letters.

(4) Rainwater catchment systems shall be marked in accordance with this section with the words: “CAU TION: NONPOTABLE RAINWATER, DO NOT DRINK” in black letters.

Exception: [DWR] For recycled water supply systems that are within or a part of a building, the provisions of Section 1505.7 shall apply.

TABLE 601.3.2

MINIMUM LENGTH OF COLOR FIELD AND SIZE OF LETTERS

OUTSIDE DIAMETER OF PIPE OR COVERING (inches)	MINIMUM LENGTH OF COLOR FIELD (inches)	MINIMUM SIZE OF LETTERS (inches)
1⁄2 to 11⁄4	8	1⁄2
11⁄2 to 2	8	3⁄4
21⁄2 to 6	12	11⁄4
8 to 10	24	21⁄2
Over 10	32	31⁄2

For SI units: 1 inch = 25.4 mm

CPC § 601.2.1.1 High relevance — show source text
601.2.1.1 Approved Submeters. [HCD 1] Sub- meters (or meters) shall be approved in accordance with the Business and Professions Code, Division 5.

601.2.1.2 Submeter Testing. [HCD 1] Submeter (or meter) testing shall be in accordance with the California Code of Regulations, Title 4, Division 9, Chapter 3, Article 1; Civil Code, Division 3, Part 4, Title 5; and Business and Professions Code, Divi- sion 5.

601.2.2 Hot and Cold Water Required. In occupancies where plumbing fixtures are installed for private use, hot water shall be required for bathing, washing, laundry, cooking purposes, dishwashing or maintenance. In occupancies where plumbing fixtures are installed for public use, hot water shall be required for bathing and washing purposes. This requirement shall not supersede the requirements for individual temperature control limitations for public lavatories and public and private bidets, bathtubs, whirlpool bathtubs, and shower control valves.

601.3 Identification of a Potable and Nonpotable Water System. In buildings where potable water and nonpotable water systems are installed, each system shall be clearly identified in accordance with Section 601.3.1 through Section 601.3.5.

601.3.1 Potable Water. Green background with white lettering.

601.3.2 Color and Information. Each system shall be identified with a colored pipe or band and coded with paints, wraps, and materials compatible with the piping.

Except as required by Section 601.3.3, nonpotable water systems shall have a yellow background with black uppercase lettering, with the words “CAUTION: NONPOTABLE WATER, DO NOT DRINK.” Each nonpotable system shall be identified to designate the liquid being conveyed, and the direction of normal flow shall be clearly shown. The minimum size of the letters and length of the color field shall comply with Table 601.3.2.

[HCD 1 & HCD 2] An international symbol of a glass in a circle with a slash through it shall be provided sim- ilar to that shown in Figure 601 for all nonpotable water

systems.

2025 CALIFORNIA PLUMBING CODE 137

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WATER SUPPLY AND DISTRIBUTION

FIGURE 601

INTERNATIONAL SYMBOL

The background color and required information shall be indicated every 20 feet (6096 mm) but not less than once per room, and shall be visible from the floor level.

601.3.3 Alternate Water Sources. Alternate water source systems shall have a purple (Pantone color No. 512, 522C, or equivalent) background with uppercase lettering and shall be field or factory marked as follows:

(1) Gray water systems shall be marked in accordance with this section with the words “CAUTION: NONPOTABLE GRAY WATER, DO NOT DRINK” in black letters.

CPC § 0.293 High relevance — show source text

For SI units: 1000 British thermal units per hour = 0.293 kW

1203.3 Tankless Water Heaters. Tankless water heaters used in space-heating applications shall be rated by the manufacturer for space-heating applications, and the output performance shall be determined by the temperature rise and flow rate of water through the unit. The ratings shall be expressed by the water temperature rise at a given flow rate. Manufacturer’s flow rates shall not be exceeded.

1204.0 Identification of Potable and Nonpotable Water Systems. 1204.1 General. In buildings where potable water and nonpotable water systems are installed, each system shall be clearly identified in accordance with Section 1204.2 through Section 1204.7.

1204.2 Color and Information. Each system shall be identified with a colored pipe or band and coded with paint, wraps, and materials compatible with the piping. 1204.3 Potable Water. Potable water systems shall be identified with a green background with white lettering. The minimum size of letters and length of the color field shall be in accordance with Table 1204.3.

TABLE 1204.3

MINIMUM LENGTH OF COLOR FIELD AND SIZE OF LETTERS

OUTSIDE DIAMETER OF PIPE OR COVERING (inches)	MINIMUM LENGTH OF COLOR FIELD (inches)	MINIMUM SIZE OF LETTERS (inches)
1_/2 to 11/_4	8	1_/_2
11_/_2 to 2	8	3_/_4
21_/_2 to 6	12	11_/_4
8 to 10	24	21_/_2
over 10	32	31_/_2

For SI units: 1 inch = 25.4 mm

TABLE 1203.2

WATER HEATERS

1204.4 Nonpotable Water. Nonpotable water systems shall have a yellow background with black uppercase lettering, with the words: “CAUTION: NONPOTABLE WATER, DO NOT DRINK.” Each nonpotable system shall be identified to designate the liquid being conveyed, and the direction of normal flow shall be clearly shown. The minimum size of the letters and length of the color field shall comply with Table 1204.3.

TABLE 1204.3

MINIMUM LENGTH OF COLOR FIELD AND SIZE OF LETTERS

For SI units: 1 inch = 25.4 mm

1204.5 Location of Piping Identification. The background color and required information shall be indicated every 20 feet (6096 mm) but not less than once per room, and shall be visible from the floor level.

1204.6 Flow Directions. Flow directions shall be indicated

on the system.

1204.7 Heat Transfer Fluid. Hydronic piping shall be identified with an orange background with black uppercase lettering, with the words “CAUTION: HEAT TRANSFER FLUID, DO NOT DRINK.” Each hydronic system shall be identified to designate the fluid being conveyed. The minimum size of the letters and length of the color field shall comply with Table 1204.3.

Each outlet on the hydronic piping system shall be posted with black uppercase lettering as follows:

“CAUTION: HEAT TRANSFER FLUID, DO NOT DRINK.”

CPC § 25.4 High relevance — show source text
For SI units: 1 inch = 25.4 mm

TABLE 1203.2

WATER HEATERS

1204.4 Nonpotable Water. Nonpotable water systems shall have a yellow background with black uppercase lettering, with the words: “CAUTION: NONPOTABLE WATER, DO NOT DRINK.” Each nonpotable system shall be identified to designate the liquid being conveyed, and the direction of normal flow shall be clearly shown. The minimum size of the letters and length of the color field shall comply with Table 1204.3.

TABLE 1204.3

MINIMUM LENGTH OF COLOR FIELD AND SIZE OF LETTERS

For SI units: 1 inch = 25.4 mm

1204.5 Location of Piping Identification. The background color and required information shall be indicated every 20 feet (6096 mm) but not less than once per room, and shall be visible from the floor level.

1204.6 Flow Directions. Flow directions shall be indicated

on the system.

1204.7 Heat Transfer Fluid. Hydronic piping shall be identified with an orange background with black uppercase lettering, with the words “CAUTION: HEAT TRANSFER FLUID, DO NOT DRINK.” Each hydronic system shall be identified to designate the fluid being conveyed. The minimum size of the letters and length of the color field shall comply with Table 1204.3.

Each outlet on the hydronic piping system shall be posted with black uppercase lettering as follows:

“CAUTION: HEAT TRANSFER FLUID, DO NOT DRINK.”

1204.8 Identification of Chemical Additives. In systems where chemical additives are used, documentation including the following information shall be readily accessible and maintained onsite:

(1) Concentrations

(2) Maintenance requirements

(3) Maintenance log

(4) Material Safety Data Sheet (SDS)

For SI units: 1000 British thermal units per hour = 0.293 kW

1205.0 Installation, Testing, and Inspection.

1205.1 Operating Instructions. Operating and maintenance information shall be provided to the building owner. 1205.2 Pressure Testing. System piping and components shall be tested with a pressure of not less than one and one-half times the operating pressure but not less than 100 psi (689 kPa). Piping shall be tested with water or air except that plastic pipe

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HYDRONICS

shall not be tested with air. Test pressures shall be held for a period of not less than 30 minutes with no perceptible drop in pressure. These tests shall be made in the presence of the Authority Having Jurisdiction.

Exceptions: (1) For PEX, PP-R, PP-RCT, PEX-AL-PEX, PE-RT, and PEAL-PE piping systems, testing with air shall be permitted where authorized by the manufacturer’s instructions for the PEX, PP-R, PP-RCT, PEX-AL-PEX, PE-RT, and PE-ALPE pipe and fittings products, and air testing is not prohibited by applicable codes, laws, or regulations outside this code.

CPC § 1505.7 High relevance — show source text

(3) On-site treated water systems shall be marked in accordance with this section with the words: “CAU TION: ON-SITE TREATED NONPOTABLE WATER, DO NOT DRINK” in black letters.

(4) Rainwater catchment systems shall be marked in accordance with this section with the words: “CAU TION: NONPOTABLE RAINWATER, DO NOT DRINK” in black letters.

Exception: [DWR] For recycled water supply systems that are within or a part of a building, the provisions of Section 1505.7 shall apply.

TABLE 601.3.2

MINIMUM LENGTH OF COLOR FIELD AND SIZE OF LETTERS

OUTSIDE DIAMETER OF PIPE OR COVERING (inches)	MINIMUM LENGTH OF COLOR FIELD (inches)	MINIMUM SIZE OF LETTERS (inches)
1⁄2 to 11⁄4	8	1⁄2
11⁄2 to 2	8	3⁄4
21⁄2 to 6	12	11⁄4
8 to 10	24	21⁄2
Over 10	32	31⁄2

For SI units: 1 inch = 25.4 mm

601.3.4 Fixtures. Where vacuum breakers or backflow preventers are installed with fixtures listed in Chapter 17, identification of the discharge side shall be permitted to be omitted.

601.3.5 Outlets. Each outlet on the nonpotable water line that is used for special purposes shall be posted with black uppercase lettering as follows: “CAUTION: NONPOTABLE WATER, DO NOT DRINK.”

601.4 Schools of Cosmetology and Cosmetological Establishments. [CA]

601.4.1 Hot- and Cold-Running Water. At least one sink with hot-and cold-running water shall be provided in each work area or workroom where hairdressing is performed in each school and establishment. 601.4.2 Handwashing Facilities. Each school and establishment shall provide adequate handwashing facil- ities, including hot-and cold-running water, located within or adjacent to the toilet room or rooms in accor- dance with Table 422.1.

601.4.3 Drinking Water. Each school and establishment shall supply potable drinking water convenient to students, patrons and employees. Approved sanitary drinking foun- tains shall be installed and so regulated that a jet of at least 2 inches (51 mm) shall be constantly available.

601.5 Meat and Poultry Processing Plants. [AGR] Except as provided in Section 601.5.4, the water supply shall be ample and potable, with adequate pressure and facilities for its distribution in the plant, and its protection against con- tamination and pollution.

CPC § 603.5.9 High relevance — show source text
603.5.9 Aspirators. Water inlets to water-supplied aspirators shall be equipped with a vacuum breaker installed in accordance with its listing requirements and this chapter. The discharge shall drain through an air gap. Where the tailpiece of a fixture to receive the discharge of an aspirator is used, the air gap shall be located above the flood-level rim of the fixture.

603.5.10 Steam or Hot Water Boilers. Potable water connections to steam or hot water boilers shall be protected from backflow by a double check valve backflow prevention assembly, backflow preventer with intermediate atmospheric vent and pressure reducing valve, or reduced pressure principle backflow prevention assembly in accordance with Table 603.2. Where chemicals are introduced into the system a reduced pressure principle backflow prevention assembly shall be provided in accordance with Table 603.2.

603.5.11 Nonpotable Water Piping. In cases where it is impractical to correct individual cross-connections on the domestic waterline, the line supplying such outlets

shall be considered a nonpotable water line. No drinking or domestic water outlets shall be connected to the nonpotable waterline. Where possible, portions of the nonpotable waterline shall be exposed, and exposed portions shall be properly identified in a manner satisfactory to the Authority Having Jurisdiction. Each outlet on the nonpotable waterline that is permitted to be used for drinking or domestic purposes shall be posted: “CAUTION: NONPOTABLE WATER, DO NOT DRINK.”

[HCD 1 & HCD 2] An international symbol of a glass in a circle with a slash through it shall be provided sim- ilar to that shown in Figure 601.

603.5.12 Beverage Dispensers. Potable water supply to carbonated beverage dispensers shall be protected by an air gap or a vented backflow preventer that complies with ASSE 1022. For carbonated beverage dispensers, piping material installed downstream of the backflow preventer shall not be affected by carbon dioxide gas. Non-carbonated beverage dispensers, such as ice makers and coffee machines, shall be protected by an air gap or dual check backflow preventer that comply with ASSE 1032 or ASSE 1024.

603.5.13 Deck-Mounted and Equipment- Mounted Vacuum Breakers. Deck-mounted or equipment-mounted vacuum breakers shall be installed in accordance with their listing and the manufacturer’s installation instructions, with the critical level not less than 1 inch (25.4 mm) above the flood-level rim.

603.5.14 Protection from Fire Systems.

Note: Fire Protection Systems has not been adopted by the State Fire Marshal. This section cannot be adopted or enforced pursuant to California Health and Safety Code 13114.7(a), which is being cited for reference. California Health and Safety Code 13114.7.

(a) For the purposes of this section the following are definitions of class I and class II systems:

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WATER SUPPLY AND DISTRIBUTION
CPC § 25.4 High relevance — show source text
2 Vertical walls, ribs, or similar obstructions extending from the water surface to or above the horizontal plane of the spout opening other than specified in Footnote 1 above. The effect of three or more such vertical walls or ribs has not been determined. In such cases, the air gap shall be measured from the top of the wall. 3 The effective opening shall be the minimum cross-sectional area at the seat of the control valve or the supply pipe or tubing that feeds the device or outlet. Where two or more lines supply one outlet, the effective opening shall be the sum of the cross-sectional areas of the individual supply lines or the area of the single outlet, whichever is smaller. 4 Air gaps less than 1 inch (25.4 mm) shall be approved as a permanent part of a listed assembly that has been tested under actual backflow conditions with vacuums of 0 to 25 inches of mercury (85 kPa).

603.5.7 Outlets with Hose Attachments. Potable water outlets with hose attachments, other than water heater drains, boiler drains, and clothes washer connections, shall be protected by a nonremovable hose bibbtype backflow preventer, a nonremovable hose bibb-type vacuum breaker, or by an atmospheric vacuum breaker installed not less than 6 inches (152 mm) above the highest point of usage located on the discharge side of the last valve. In climates where freezing temperatures occur, a listed self-draining frost-proof hose bibb with an integral backflow preventer or vacuum breaker shall be used. 603.5.8 Water-Cooled Equipment. Water-cooled compressors, degreasers, or other water-cooled equipment shall be protected by a backflow preventer installed in accordance with the requirements of this chapter. Water-cooled equipment that produces backpressure shall be equipped with the appropriate protection. 603.5.9 Aspirators. Water inlets to water-supplied aspirators shall be equipped with a vacuum breaker installed in accordance with its listing requirements and this chapter. The discharge shall drain through an air gap. Where the tailpiece of a fixture to receive the discharge of an aspirator is used, the air gap shall be located above the flood-level rim of the fixture.

603.5.10 Steam or Hot Water Boilers. Potable water connections to steam or hot water boilers shall be protected from backflow by a double check valve backflow prevention assembly, backflow preventer with intermediate atmospheric vent and pressure reducing valve, or reduced pressure principle backflow prevention assembly in accordance with Table 603.2. Where chemicals are introduced into the system a reduced pressure principle backflow prevention assembly shall be provided in accordance with Table 603.2.

603.5.11 Nonpotable Water Piping. In cases where it is impractical to correct individual cross-connections on the domestic waterline, the line supplying such outlets

shall be considered a nonpotable water line. No drinking or domestic water outlets shall be connected to the nonpotable waterline. Where possible, portions of the nonpotable waterline shall be exposed, and exposed portions shall be properly identified in a manner satisfactory to the Authority Having Jurisdiction. Each outlet on the nonpotable waterline that is permitted to be used for drinking or domestic purposes shall be posted: “CAUTION: NONPOTABLE WATER, DO NOT DRINK.”

[HCD 1 & HCD 2] An international symbol of a glass in a circle with a slash through it shall be provided sim- ilar to that shown in Figure 601.
California Plumbing Code High relevance — show source text
3/8″
main reinforcement bars at 57/8″ pitch
with7/8″ concrete cover;3/8″ main rein-
forcement bars at 41/2″ pitch
perpendicular with1/2″ concrete cover;
13′1″ span restrained.|195 psf|4 hrs|||7|1, 7|4| |F/C-4-RC-7|4″|4″ (5025 psi) concrete deck;1/4″ reinforce-
ment bars at 71/2″ pitch with3/4″ cover;3/8″
main reinforcement bars at 33/4″ pitch
perpendicular with1/2″ cover; 13′1″ span
restrained.|140 psf|1 hr
16 min|||7|1, 2|11/4| |F/C-4-RC-8|4″|4″ thick (4905 psi) deck;1/4″ reinforce-
ment bars at 71/2″ pitch with7/8″ cover;3/8″
main reinforcement bars at 33/4″ pitch
perpendicular with1/2″ cover; 13′1″ span
restrained.|100 psf|1 hr
23 min|||7|1, 2|11/3| |F/C-4-RC-9|4″|4″ deep (4370 psi);1/4″ reinforcement bars
at 6″ pitch with3/4″ cover;1/4″ main rein-
forcement bars at 4″ pitch perpendicular
with1/2″ cover; 13′1″ span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-10|4″|4″ thick (5140 psi) deck;1/4″ reinforce-
ment bars at 71/2″ pitch with7/8″ cover;3/8″
main reinforcement bars at 33/4″ pitch
perpendicular with1/2″ cover; 13′1″ span
restrained.|140 psf|1 hr
16 min|||7|1, 5|11/4| |F/C-4-RC-11|4″|4″ thick (4000 psi) concrete deck;
3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.; flush
with top surface; 4″ × 6″ x 13 SWG mesh
reinforcement 1″ from bottom of slab; 6′6″
span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-12|4″|4″ deep (2380 psi) concrete deck;
3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.
CPC § 1504.9.1 High relevance — show source text
Future connections . . . . . . . . . . . . . . . . . . . . .1504.9.1

Identification of piping . . . . . . . . . . . . . . . . . . . . .601.3.3 Nonpotable rainwater catchment system . . . . . . . . . . .Table 1601.5, 1602.4

Potable rainwater

catchment system . . . . . . . . . . . . . . . . . . . . . .K 102.2 ANODELESS RISER, DEFINITION . . . . . . . . . . . . . . .203.0

APPLIANCES

Automatically operated . . . . . . . . . . . .509.3.4, 509.5.7.1 Categorized vent diameter/area, definition . . . . . . . . . . . . . . . . . .203.0 Connections to building fuel gas piping . . . . . . . . . . . . . . . . . . . . . . . . .1212.0

Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203.0

Direct-vent . . . . . . . . . . . . . . . .206.0, 509.2.6, 509.5.10.1,

509.8.1, 509.12

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INDEX

In attics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .508.4

Indirect waste type . . . . . . . . . . . . . . . . . . .806.0, 807.0

In under-floor spaces . . . . . . . . . . . . . . . . . . . . . . .508.4

On roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .508.0

Vent Connectors . . . . . . . . . . . . . . . . . .509.10, 510.2.11

Venting of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .509.0

APPLICATION FOR PERMIT . . . . . . . . . . . . . . . . . . .104.3

APPROVED, DEFINITION . . . . . . . . . . . . . . . . . . . . . .203.0

APPROVED TESTING

AGENCY, DEFINITION . . . . . . . . . . . . . . . . . . . . . . .203.0

AREA DRAINS . . . . . . . . . . . . . . . . . . . . . . . .203.0, 1101.15

ASBESTOS-CEMENT PIPE . . . . . . . . . . . .Table 510.1.2(5),
CPC § 1501.9. Medium relevance — show source text
“TO CONSERVE WATER, THIS BUILDING USES ON-SITE TREATED NONPOTABLE GRAYWATER TO

FLUSH TOILETS AND URINALS.”

1501.9. 2 Equipment Room Signs. Each room containing on-site treated nonpotable gray water equipment shall have a sign posted in a location that is visible to anyone working on or near nonpotable gray water equipment with the following wording in 1 inch (25.4 mm) letters:

“CAUTION: ON-SITE TREATED NONPOTABLE GRAY-

WATER, DO NOT DRINK. DO NOT CONNECT TO DRINKING WATER SYSTEM. NOTICE: CONTACT

BUILDING MANAGEMENT BEFORE PERFORMING

ANY WORK ON THIS WATER SYSTEM.”

1501.10 System Controls. Controls for pumps, valves, and other devices that contain mercury that come in contact with alternate water source water supply shall not be permitted.

1502.0 Inspection and Testing.

1502.1 General. Alternate water source systems shall be inspected and tested in accordance with Section 1502.2 through Section 1502.3.3, and/or as required by the Author- ity Having Jurisdiction .

Exception: [DWR] Recycled water supply systems that are within or a part of a building shall comply with Section 1505.14.

1502.2 Supply System Inspection and Test. Alternate water source systems shall be inspected and tested in accordance with this code for testing of potable water piping.

1502.3 Cross-Connection Inspection and Testing. An initial visual inspection and initial cross-connection test shall be performed on both the potable and alternate water source systems before the initial operation of the alternate water source system. During an initial or subsequent cross-con- nection test, the potable and alternate water source system shall be isolated from each other and independently inspected and tested to ensure there is no cross-connection in accor dance with Section 1502.3.1 through Section 1502.3.3 .

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ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

1502.3.1 Visual System Inspection. Before commencing the cross-connection testing, a dual system inspection shall be conducted by the Authority Having Jurisdiction and other authorities having jurisdiction as follows:

(1) Meter locations of the alternate water source and potable water lines shall be checked to verify that no modifications were made and that no cross-con nections are visible.

(2) Pumps and equipment, equipment room signs and exposed piping in equipment room shall be checked.

(3) Valves shall be checked to ensure that the valve lock seals are still in place and intact. Valve control door signs shall be checked to verify that no signs have been removed.

1502.3.2 Cross-Connection Test. A cross-connec- tion test shall be performed in the presence of the Authority Having Jurisdiction or other authorities having jurisdiction to determine whether a cross-connection has occurred as follows:

(1) The potable water system shall be activated and pressurized. The alternate water source system shall be shut down, depressurized, and drained.
CPC § 1601.3 Medium relevance — show source text
2
1601.3 & Exceptions 1 & 2
1601.5
1601.6
1601.7
1602.4_& Exceptions_
1602.7
1603.3
1603.3.1 &Exception
1603.4
1603.4.1
Table 1603.4
1603.7
1603.8
1603.9
1603.10_A & B_
1603.12
1603.20
1604.1 - 1604.3
1605.3
1605.3.2
1605.3.3|X|||X||||||||||||||||||||| |Adopting Agency
Adopt Entire Chapter
Adopt Entire Chapter as
amended (amended
sections listed below)
Adopt only those sections
that are listed below
Chapter/Section
1601.2
1601.3 & Exceptions 1 & 2
1601.5
1601.6
1601.7
1602.4_& Exceptions_
1602.7
1603.3
1603.3.1 &Exception
1603.4
1603.4.1
Table 1603.4
1603.7
1603.8
1603.9
1603.10_A & B_
1603.12
1603.20
1604.1 - 1604.3
1605.3
1605.3.2
1605.3.3|X|||X|||||||||||||||||||||

This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

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CHAPTER 16

NONPOTABLE RAINWATER CATCHMENT SYSTEMS

1601.0 General.

1601.1 Applicability. The provisions of this chapter shall apply to the installation, construction, alteration, and repair of nonpotable rainwater catchment systems.

1601.1.1 Allowable Use of Alternate Water. Where approved or required by the Authority Having Jurisdiction, rainwater shall be permitted to be used instead of potable water for the applications identified in this chap ter.

1601.2 System Design. Rainwater catchment systems shall be designed in accordance with this chapter by a person registered or licensed to perform plumbing design work or who demonstrates competency to design the rainwater catchment system as required by the Authority Having Jurisdiction . Components, piping, and fittings used in a rainwater catchment system shall be listed.
CPC § 601.2.1 Medium relevance — show source text
(6) [DWR] Where a public agency requires a building to use recycled water to flush water closets and urinals in accordance with California Water Code 13554. 601.2.1 Submeters. [HCD 1] Submeters (or meters) shall be installed to measure potable and reclaimed (recycled) water (hot and cold) that is supplied for the exclusive use of an individual dwelling unit within a newly constructed, multiunit rental residential structure; or for the use of an individual dwelling unit within a newly constructed mixed-use rental residential/commer- cial structure. Submeters (or meters) shall be installed in accordance with this code and the manufacturer’s installation instructions.

See Water Code Section 517 for definitions of “multiunit residential structure” and “mixed-use resi-

dential and commercial structure.” See also Civil Code commencing with Section 1954.201.

Exemptions:

(1) Long-term health care facilities as defined in Health and Safety Code Section 1418.

(2) Low-income housing as defined in Health and Safety Code Section 17922.14 (c)(2)(B).

(3) Residential care facilities for the elderly as defined in Health and Safety Code Section 1569.2 (p)(1).

(4) Housing at a place of education as defined in Title 24 of the California Code of Regulations, Califor- nia Building Code, Part 2, Section 202.

(5) Time-share property as defined in Business and Pro- fessions Code Section 11212, Subdivision (aa).

601.2.1.1 Approved Submeters. [HCD 1] Sub- meters (or meters) shall be approved in accordance with the Business and Professions Code, Division 5.

601.2.1.2 Submeter Testing. [HCD 1] Submeter (or meter) testing shall be in accordance with the California Code of Regulations, Title 4, Division 9, Chapter 3, Article 1; Civil Code, Division 3, Part 4, Title 5; and Business and Professions Code, Divi- sion 5.

601.2.2 Hot and Cold Water Required. In occupancies where plumbing fixtures are installed for private use, hot water shall be required for bathing, washing, laundry, cooking purposes, dishwashing or maintenance. In occupancies where plumbing fixtures are installed for public use, hot water shall be required for bathing and washing purposes. This requirement shall not supersede the requirements for individual temperature control limitations for public lavatories and public and private bidets, bathtubs, whirlpool bathtubs, and shower control valves.

601.3 Identification of a Potable and Nonpotable Water System. In buildings where potable water and nonpotable water systems are installed, each system shall be clearly identified in accordance with Section 601.3.1 through Section 601.3.5.

601.3.1 Potable Water. Green background with white lettering.

601.3.2 Color and Information. Each system shall be identified with a colored pipe or band and coded with paints, wraps, and materials compatible with the piping.
CPC § 909.12.4 High relevance — show source text
[F] 909.12.4 Automatic control. Where completely automatic control is required or used, the automatic-control sequences shall be initiated from an appropriately zoned automatic sprinkler system complying with Section 903.3.1.1, manual controls provided with ready access for the fire department and any smoke detectors required by engineering analysis.

[F] 909.13 Control air tubing. Control air tubing shall be of sufficient size to meet the required response times. Tubing shall be flushed clean and dry prior to final connections and shall be adequately supported and protected from damage. Tubing passing through concrete or masonry shall be sleeved and protected from abrasion and electrolytic action.

[F] 909.13.1 Materials. Control-air tubing shall be hard-drawn copper, Type L, ACR in accordance with ASTM B42, ASTM B43, ASTM B68/B68M, ASTM B88, ASTM B251 and ASTM B280. Fittings shall be wrought copper or brass, solder type in accordance with ASME B16.18 or ASME B16.22. Changes in direction shall be made with appropriate tool bends. Brass compression-type fittings shall be used at final connection to devices; other joints shall be brazed using a BCuP-5 brazing alloy with solidus above 1,100°F (593°C) and liquids below 1,500°F (816°C). Brazing flux shall be used on copper-to-brass joints only.

Exception: Nonmetallic tubing used within control panels and at the final connection to devices provided that all of the following conditions are met:
1. Tubing shall comply with the requirements of Chapter 6 of the California Mechanical Code .
2. Tubing and connected devices shall be completely enclosed within a galvanized or paint-grade steel enclosure having a minimum thickness of 0.0296 inch (0.7534 mm) (No. 22 gage). Entry to the enclosure shall be by copper tubing with a protective grommet of neoprene or Teflon or by suitable brass compression to male barbed adapter.
3. Tubing shall be identified by appropriately documented coding.
4. Tubing shall be neatly tied and supported within the enclosure. Tubing bridging cabinets and doors or moveable devices shall be of sufficient length to avoid tension and excessive stress. Tubing shall be protected against abrasion. Tubing connected to devices on doors shall be fastened along hinges.
[F] 909.13.2 Isolation from other functions. Control tubing serving other than smoke control functions shall be isolated by automatic isolation valves or shall be an independent system.

[F] 909.13.3 Testing. Control air tubing shall be tested at three times the operating pressure for not less than 30 minutes without any noticeable loss in gauge pressure prior to final connection to devices.

[F] 909.14 Marking and identification. The detection and control systems shall be clearly marked at all junctions, accesses and terminations.

[F] 909.15 Control diagrams. Identical control diagrams showing all devices in the system and identifying their location and function shall be maintained current and kept on file with the fire code official, the fire department and in the fire command center in a format and manner approved by the fire code official.
CPC § 123.5 Medium relevance — show source text
**
HOURS| |ITEM
CODE|MINIMUM
DIMENSION|CONSTRUCTION DETAILS|LOAD|TIME|PRE-BMS-92|BMS-92|POST-BMS-92|POST-BMS-92|POST-BMS-92| |C-16-RC-2|16″|16″ square columns; gravel aggregate concrete
(3360 psi); reinforcement: vertical, eight 13/8″
rebars; horizontal,5/16″ ties at 6″ pitch; cover:
13/8″.|210
tons|2 hrs|||7|2,
4–6|2| |C-16-RC-3|16″|16″ square columns; gravel aggregate concrete
(3980 psi); reinforcement: vertical, four7/8″
rebars; horizontal,3/8″ ties at 6″ pitch; cover:
1″.|123.5
tons|2 hrs|||7|2, 4,
7|2| |C-16-RC-4|16″|Reinforced concrete columns with 11/2″
concrete outside reinforcing steel; gross diam-
eter or side of column: 16″; Group I, Column A.|—|9 hrs||1||8, 9|9| |C-16-RC-5|16″|Description as per C-16-RC-4;
Group I, Column B.|—|6 hrs||1||8, 9|6| |C-16-RC-6|16″|Description as per C-16-RC-4;
Group II, Column A.|—|6 hrs||1||8, 9|6| |C-16-RC-7|16″|Description as per C-16-RC-4;
Group II, Column B.|—|4 hrs||1||8, 9|4| |C-16-RC-8|16″|Description as per C-16-RC-4;
Group III, Column A.|—|5 hrs||1||8, 9|5| |C-16-RC-9|16″|Description as per C-16-RC-4;
Group III, Column B.|—|3 hrs
30 min||1||8, 9|31/2| |C-16-RC-
10|16″|Description as per C-16-RC-4;
Group IV, Column A.|—|3 hrs||1||8, 9|3| |C-16-RC-
11|16″|Description as per C-16-RC-4;
Group IV, Column B.|—|2 hrs||1||8, 9|2|

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 0.00689 MPa, 1 pound per square yard = 5.3 N/m [2] .

Notes:
1. Column passed 1-hour fire test.
2. Column passed hose stream test.
3. No reload specified.
4. Column passed 2-hour fire test.
5. Column reloaded successfully after 24 hours.
6. Reinforcing details same as C-16-RC-1.
7. Column passed reload after 72 hours.
CPC § 1505.16 Medium relevance — show source text
0 - 1505.16|†|†||†||||||||||||||||X||||| |Figure 1505.10||||||||||||||||||||X||||| |Table 1505.16||†||†||||||||||||||||X||||| |1506.0 - 1506.4 Exceptions||X||X||||||||||||||||||||| |1506.4 & Exceptions||||||||||||||||||||X||||| |1506.5||X||X||||||||||||||||||||| |1506.6 -1506.10.6||X||X||||||||||||||||||||| |1506.12||X||X|X|||||||||||||||||||| |1506.13||X||X|||||||||||||||||||||

This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

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CHAPTER 15

ALTERNATE WATER SOURCES FOR NONPOTABLE APPLICATIONS

1501.0 General.

1501.1 Applicability. [BSC-CG, DWR & HCD 1] The provisions of this chapter shall apply to the construction, alteration, discharge, use and repair of alternate water source systems for nonpotable applications.

1501.1.1 Allowable Use of Alternate Water. Where approved or required by the Authority Having Jurisdiction, alternate water sources [reclaimed (recycled) water, gray water, and on-site treated nonpotable gray water] shall be permitted to be used instead of potable water for the applications identified in this chapter. 1501.2 System Design. [BSC-CG, HCD 1 & DWR] Alternate water source systems shall be designed in accordance with this chapter by a registered design professional or licensed person who demonstrates competency to design the alternate water source system as required by the Authority Having Jurisdiction . Components, piping, and fittings used in any alternate water source system shall be listed.

[BSC-CG & HCD 1] Irrigation design plans shall meet the requirements of the California Code of Regulations, Title 23, Division 2, Chapter 2.7, Model Water Efficient Landscape Ordinance.

Exceptions:

(1) A registered design professional or a licensed person who demonstrates competency to design the alternate water source system is not required to design gray water systems having a maximum discharge capacity of 250 gallons per day (gal/d) (0.011 L/s) for single family and multi-family dwellings.

(2) A registered design professional or a licensed person who demonstrates competency to design the alternate water source system is not required to design an on-site treated nonpotable water system for single-family dwellings having a maximum discharge capacity of 250 gal/d (0.011 L/s).

**1501.3 Permit.
CPC § 1604.1 High relevance — show source text
20
1604.1 - 1604.3
1605.3
1605.3.2
1605.3.3|X|||X|||||||||||||||||||||

This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

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CHAPTER 16

NONPOTABLE RAINWATER CATCHMENT SYSTEMS

1601.0 General.

1601.1 Applicability. The provisions of this chapter shall apply to the installation, construction, alteration, and repair of nonpotable rainwater catchment systems.

1601.1.1 Allowable Use of Alternate Water. Where approved or required by the Authority Having Jurisdiction, rainwater shall be permitted to be used instead of potable water for the applications identified in this chap ter.

1601.2 System Design. Rainwater catchment systems shall be designed in accordance with this chapter by a person registered or licensed to perform plumbing design work or who demonstrates competency to design the rainwater catchment system as required by the Authority Having Jurisdiction . Components, piping, and fittings used in a rainwater catchment system shall be listed.

[HCD 1] Irrigation design plans shall meet the requirements of the California Code of Regulations, Title 23, Division 2, Chapter 2.7, Model Water Efficient Landscape Ordinance.

Exceptions:

(1) A person registered or licensed to perform plumbing design work is not required to design rainwater catchment systems used for irrigation with a maximum storage capacity of 360 gallons (1363 L).

(2) A person registered or licensed to perform plumbing design work is not required to design rainwater catchment systems for single family dwellings where outlets, piping, and system components are located on the exterior of the building.

1601.3 Permit. It shall be unlawful for a person to construct, install, alter, or cause to be constructed, installed, or altered a nonpotable rainwater catchment system in a building or on a premise without first obtaining a permit to do such work from the Authority Having Jurisdiction.

Exceptions:

(1) A permit is not required for exterior rainwater catchment systems used for outdoor non-spray irrigation with a maximum storage capacity of 5000 gallons (18 927 L) where the tank is supported directly upon grade and the ratio of height to diameter or width does not exceed 2 to 1 and it does not require electrical power or a makeup water supply connection. (2) [HCD 1 & HCD 2] A permit is not required for exterior rainwater catchment systems used for spray irrigation with a maximum storage capacity of 360 gallons (1363 L). 1601.4 Component Identification. System components shall be properly identified as to the manufacturer.
CPC § 16-3 Medium relevance — show source text
1601 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-3

1602 Notations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-3

1603 Construction Documents . . . . . . . . . . . . . . . . . . . . . . . 16-4

1604 General Design Requirements. . . . . . . . . . . . . . . . . . . 16-5

1605 Load Combinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-8

1606 Dead Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16-9

1607 Live Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-10

1608 Snow Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-18

1609 Wind Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-24

1610 Soil Loads and Hydrostatic Pressure. . . . . . . . . . . .16-31

1611 Rain Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-32

1612 Flood Loads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-33

1613 Earthquake Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-34

1614 Atmospheric Ice Loads . . . . . . . . . . . . . . . . . . . . . . . .16-36

1615 Tsunami Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-36

1616 Structural Integrity . . . . . . . . . . . . . . . . . . . . . . . . . . .16-36

1617 Additional Requirements for Community Colleges [DSA-SS/CC] . . . . . . . . . . . . . 16-38

CHAPTER 16A STRUCTURAL DESIGN. . . . . . . . . . . . . . . . . 16A-1

1601A General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16A-3

1602A Notations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16A-3

Frequently asked questions

Who decides the final appearance/placement of markings if piping is concealed?

The Authority Having Jurisdiction (AHJ) can require exposed portions or other acceptable identification methods when full marking isn’t practical; identification must be “satisfactory to the AHJ.” See § 603.5.11.

Can reclaimed/recycled water used outdoors use yellow markings?

No — reclaimed (recycled) water systems for outdoor applications must be purple and use the reclaimed‑water wording listed in § 601.3.3.

How often do I need to repeat the label on a long run of pipe?

Labels must be visible from floor level and repeated every 20 ft (6096 mm) or not less than once per room, per § 601.3.2.

What size letters do I use for small 1" OD tubing?

Follow Table 601.3.2: for 1/2"–1-1/4" OD, use a minimum color field length of 8 inches and minimum letter size of 1/2 inch. See § 601.3.2.

Is an international “do not drink” symbol required?

Yes — the CPC references an international symbol (glass with a slash) for nonpotable systems; see the Figure referenced in § 601.3 (and § 601.3.2).

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