AnalyteSystemMethod/ChemistryStandard/Equivalance or DescriptionComparatorCellPhosphateColor Card comparatorStannous chloride (commercial use only)0, 50, 125, 250, 500, 1000 ppb PO₄³ˉ54344025PhosphateColor Card comparatorStannous chloride (commercial use only)0, 250, 1000, 2000, 4000, 6000 ppb PO₄³ˉ54354025 ...