(1) In the design of a new or expanding Group B system, all materials in contact with potable water shall conform to the ANSI/NSF Standard 61.

(2) Pipes, pipe fittings, fittings, fixtures, solder, or flux used in the design of a new or expanding Group B system shall be lead-free. For the purposes of this section, lead-free means:

(a) Not more than a weighted average of twenty-five one-hundredths of one percent lead for wetted surfaces of pipes and pipe fittings; and

(b) No more than two-tenths of one percent lead in solder and flux.

(3) Any chemicals specified for use in the design of treatment for secondary MCLs in Table 3 under WAC 246-291-170, with the exception of unscented commercial grade hypochlorite compounds, shall comply with ANSI/NSF Standard 60. The design dosage shall not exceed the maximum application dosage recommended for the product as certified by the ANSI/NSF Standard 60.

(4) The department may review and approve the use of materials or additives that are not ANSI/NSF Standard 60 or 61 certified on a case-by-case basis.