All measurements, tests and analyses of the characteristics of waters and wastes shall be determined in accordance with the latest edition of "Standard Methods for the Examination of Water and Wastewater," published by the American Public Health Association, and shall be determined at the control manhole provided, or upon suitable samples taken at the control manhole. The control manhole shall be located so that sampling of the industrial waste will be performed before discharge into the public sewerage system. Sampling shall be carried out by customarily accepted methods to reflect the effect of constituents upon the sewage works and to determine the existence of hazards to life, limb and property. (The particular analyses involved will be determined whether a twenty-four-hour composite of all outfalls of a premises is appropriate or whether a grab sample or samples should be taken. Normally, but not always, COD and settleable solids analyses are obtained from twenty-four-hour composites of all outfalls whereas pHs are determined from periodic grab samples.) (Prior code § 4-3-47 (12))