scope:

This International Standard specifies methods for the determination of - orthophosphate (see Clause 4); - orthophosphate after solvent extraction (see Clause 5); - hydrolysable phosphate plus orthophosphate (see Clause 6); - total phosphorus after decomposition (see Clauses 7 and 8). The methods are applicable to all kinds of water including seawater and effluents. Phosphorus concentrations within the range of 0,005 mg/l to 0,8 mg/l may be determined in such samples without dilution. A solvent extraction procedure allows smaller phosphorus concentrations to be determined with a detection limit of about 0,000 5 mg/l.