Further Study of Permanent Color Comparator for Fluorides: Task Group Report

Abstract

Since the publication of the 1957 report by AWWA Task Group 2620 P ‐ Fluoridation Materials and Methods, the manufacturer has made available a modified version of its fluoride testing kit. The modifications include a new slide containing permanent color standards in vials, longer analyzer tubes, and the use of the Scott‐Sanchis reagent, which supplants the one developed by Lamar. The new tubes and slide fit are intended to be used in the older “water analyzer” apparatus. With the announcement of the availability of this modification, AWWA furnished the new parts and reagents to each member of the original task group, which was to evaluate the new kit. The purpose of this study was to determine, as before, the conditions that would produce optimum accuracy in the fluoride determination, and also the factors that could produce results more inaccurate than those obtainable from the procedures found in Standard Methods.