(1) Section 34 and section 35 do not apply to the addition by the responsible utility to a water network of—
(a) a chemical for the purpose of clarifying, purifying or otherwise treating the water in that network at a concentration that is not injurious to public health; or
(b) fluoride at a concentration not exceeding 1.0mg/L.
(2) For subsection (1) (b), a concentration is taken to be a concentration of 1.0mg/L if the concentration—
(a) would result in an average concentration of 1.0mg/L during a period of 24 hours; and
(b) does not exceed 1.2mg/L.