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.