Revised Standard from Last Update.

NATIONAL FOREWORD

This Indian Standard (Part 1) (First Revision) which is identical with ISO 12858-1 : 2014 ‘Optics and optical instruments — Ancillary devices for geodetic instruments — Part 1: Invar levelling staffs’ issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on recommendation of the Educational Instruments and Equipment Sectional Committee and approval of the Production and General Engineering Division Council.

This standard was originally published in 2004 and was identical with ISO 12858-1 : 1999. The first revision of this standard has been undertaken to align it with the latest version of ISO 12858-1 : 2014.

This Indian Standard is published in two parts. The other part of this standard are:

Part 2 Tripods

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.