BS ISO 11943:2021

This standard BS ISO 11943:2021 Hydraulic fluid power. Online automatic particle-counting systems for liquids. Methods of calibration and validation is classified in these ICS categories:

• 23.100.01 Fluid power systems in general
• 23.100.60 Filters, seals and contamination of fluids

This document establishes methods for:

1. validating equipment used to prepare secondary calibration suspensions for automatic particle counters;

2. performing online secondary calibration of automatic particle counters;

3. matching two or more online particle counters, i.e. to count the same number of particles at a given size by two APCs associated online;

4. validating online particle counting systems with and without online dilution as used, for example, to measure the filtration efficiency of a hydraulic filter as described in the multi-pass filter test in ISO 16889 .