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Total Phosphorus Calculator

Total Phosphorus Calculator

Definition: Total phosphorus includes phosphorus present in dissolved and particulate forms. After appropriate digestion, phosphorus is converted to reactive orthophosphate and measured colorimetrically.

Total P (mg/L as P) = [(A − b) / m] × DF

A = absorbance of digested sample
b = calibration curve intercept
m = calibration curve slope
DF = overall dilution factor

Method basis: Standard Methods for the Examination of Water and Wastewater, 4500-P B — Sample Preparation, followed by 4500-P E — Ascorbic Acid Method.