Reaffirmed 2023

NATIONAL FOREWORD

This Indian Standard which is identical with ISO 4325 : 1990 ‘Soaps and detergents — Determination of chelating agent content — Titrimetric method’ issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on recommendation of the Soaps and other surface active agents Sectional Committee and approval of the Chemical Division Council.

Removal of soiling by use of soap and detergent is a complex process and involves more than just adding soap or surfactant to water. One of the major concerns is water hardness due to the presence of calcium, magnesium, iron and manganese metal ions. These metal ions interfere with the cleaning ability of detergents. A chelating agent combines itself with these disruptive metal ions in the water. This makes it impossible for the metal ions to be precipitated with the surfactants. Thus, chelated metal ions remain tied up in solution in a harmless state where they will not use up the surfactants. While adopting ISO standards on different test methods, it is observed that there is no Indian standard on determination of chelating agent content in surfactants. Considering the importance of test method for determination of chelating agent content in soaps and detergents and to follow the uniform practices globally, the Committee felt that it would be more convenient to prepare this standard method by adoption of ISO 4325 on dual number basis. This method is titrimetric method.

The text of ISO Standard has been approved as suitable for publication as an Indian Standard without deviations. Certain terminologies and conventions are, however, not identical to those used in Indian Standards. Attention is particularly drawn to the following:

a) Wherever the words ‘International Standard’ appear referring to this standard, they should be read as ‘Indian Standard’.

b) Comma (,) has been used as a decimal marker, while in Indian Standards, the current practice is to use a point (.) as the decimal marker.