Revised Standard from Last Update.

1. SCOPE

This standard describes two following methods for the determination of total and dissolved sulphides in waters and waste waters:

a) Titrimetric iodine method or methylene blue method, based on the reaction of sulphide, ferric chloride and dimethyl-p-phenylenediamine to produce methylene blue. Ammonium phosphate is added after colour development to remove ferric chloride colour. The procedure is applicable at sulphide concentration between 2 and 20 mg/l; and

b) Iodometric method, is suitable for measurement of sulphide in concentration above 1 mg/l if interferences are absent and loss of hydrogen sulphide is avoided. The iodometric method is useful for standardizing the methylene blue colorimetric method and is suitable for analyzing samples freshly taken from wells or springs.

2. REFERENCES

17614 (Part 1) : 2021 Water quality - Sampling: Part 1 Guidance on the design of sampling programmes and sampling techniques

17614 (Part 3) : 2021 Water quality - Sampling: Part 3 Preservation and handling of water samples