NATIONAL FOREWORD

This Indian Standard (Part 3) (Second Revision) which is identical with ISO 4047 : 1977 ‘Leather — Determination of sulphated total ash and sulphated water-insoluble ash issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on the recommendation of the Leather, Tanning Material and Allied Products Sectional Committee and approval of the Chemical Division Council.

The Indian Standard IS 582 : 1970 Methods of Chemical testing of leather (first revision) prescribes the methods of chemical testing for all types of leathers. The Committee responsible for formulating this standard has decided to harmonize the methods of test prescribed in IS 582 with those prescribed in ISO/IULTCS standards. Accordingly, the committee decided to retain IS 582 and publish the harmonized/adopted test methods published by ISO/IULTCS in various parts of IS 582 as this standard is widely recognized by the Indian Leather Industry.

The committee further decided to publish the adopted/harmonized standards in the following manner:

a) Wherever an existing test method is being replaced by the corresponding ISO/IULTCS test method, the relevant part will be published as revision with the information in the national foreword about the method of IS 582 being superseded.

b) When a new test method is being incorporated in IS 582, the same will be published as a new standard and as subsequent part of IS 582.

This Indian Standard (Part 3) (Second Revision) supersedes the following method of tests prescribed in IS 582 : 1970:

a) LC : 3 Determination of total ash

b) LC : 8 Determination of water insoluble ash

The text of ISO Standard has been approved as suitable for publication as an Indian Standard without deviations. Certain 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.