EPA 365.3

Phosphorous, All Forms (Colorimetric, Ascorbic Acid, Two Reagent

Applicability: EPA Method 365.3 is applicable for measuring phosphorus in various water samples, including drinking water, surface water, and domestic and industrial wastewater. It is designed to determine different forms of phosphorus, such as total phosphorus, orthophosphate, and hydrolyzable phosphorus.

Purpose: EPA Method 365.3 is used to determine phosphorus, including orthophosphate and other forms, in various water samples, including drinking water, surface water, and wastewater. The method is colorimetric and involves a reaction with ammonium molybdate and ascorbic acid to produce a blue-colored complex, with the intensity of the color indicating the phosphorus concentration.