The manufacturer of PEX tubing shall have marked the outside of the tubing with the thermoplastic material designation code in accordance with ASTM F876. The designation code shall consist of the abbreviation "PEX" followed by four digits. The first digit shall represent a chlorine resistance rating as established by testing in accordance with ASTM F876.

For PEX tubing complying with ASTM F876, the first digit folllowing "PEX" as marked on the tubing exterior shall be an indicator of the maximum service temperatures for which the PEX tubing can be used. The maximum service temperatures shall be as follows:

1. Digit “0”: 73⁰F (23⁰C).

2. Digit “1”: For not more that 25% of the time, greater than 73⁰F (23⁰C) and not exceeding140⁰F (60⁰C). For the remainder of the time, not greater than 73⁰F (23⁰C).

3. Digit “3”: For not more that 50% of the time, greater than 73⁰F (23⁰C) and not exceeding 140⁰F (60⁰C). For the remainder of the time, not greater than 73⁰F (23⁰C).

4. Digit “5”: 140⁰F (60⁰C).


The manufacturer ofFor PEX tubing shall have marked the outside of the tubing with the thermoplastic material designation code in accordancecomplying with ASTM F876. The designation code, the first digit folllowing "PEX" as marked on the tubing exterior shall consistbe an indicator of the abbreviation "maximum service temperatures for which the PEX" followed by four digits tubing can be used. The first digitmaximum service temperatures shall represent a chlorine resistance ratingbe as established by testing in accordance with ASTM F876follows:

1. Digit “0”: 73⁰F (23⁰C).

2. Digit “1”: For not more that 25% of the time, greater than 73⁰F (23⁰C) and not exceeding140⁰F (60⁰C). For the remainder of the time, not greater than 73⁰F (23⁰C).

3. Digit “3”: For not more that 50% of the time, greater than 73⁰F (23⁰C) and not exceeding 140⁰F (60⁰C). For the remainder of the time, not greater than 73⁰F (23⁰C).

4. Digit “5”: 140⁰F (60⁰C).