I. General Discussion
a. Principle: The sample of water is diluted with odor-free water until a dilution that is of the least definitely i perceptible odor to each tester is found. People vary widely as to odor sensitivity, and even the same person will not be consistent in the concentrations I be can detect from day to day. Panels of not less than five persons, and preferably 10 or more, are recommended to overcome the variability of using one observer.1 Some investigators have sought to overcome the problems involved in using one or two observers, I or to compare the