Revised Standard from Last Update.

NATIONAL FOREWORD

This Indian Standard (Third Revision) which is identical with ISO 4406 : 2021 ‘Hydraulic fluid power — Fluids — Method for coding the level of contamination by solid particles’ issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on the recommendation of Fluid Power Systems Sectional Committee and approval of the Production and General Engineering Division Council.

In hydraulic fluid power systems, power is transmitted and controlled through a liquid under pressure with in an enclosed circuit. Solid particle contaminant is always present in the hydraulic fluid and the amount needs to be determined because the contaminant can cause serious problems.

Most hydraulic component manufacturers require a certain cleanliness level for warranty purposes, to ensure proper function and for a long, trouble-free life. This IS 13542 cleanliness code acts as a means of communicating the cleanliness of a hydraulic fluid.

This standard was originally published in 1972 and subsequently revised in 2013 and 2020. This revision has been undertaken to align it with the latest version of ISO 4406.