(a) In the installation or repair of plumbing intended to dispense water for human consumption, a person shall use only pipes, pipe fittings, plumbing fittings, or fixtures that are lead-free.

(b) In the installation or repair of plumbing intended to dispense water for human consumption, a person shall use only solder or flux that is lead-free.

(c) Only the individual pipes, pipe fittings, plumbing fittings, or fixtures that are installed or repaired may be considered when calculating the weighted average lead content.