BS ISO 11171:2020

This standard BS ISO 11171:2020 Hydraulic fluid power. Calibration of automatic particle counters for liquids is classified in these ICS categories:

• 75.120 Hydraulic fluids
• 23.100.60 Filters, seals and contamination of fluids

This document specifies procedures for the following:

1. primary particle-sizing calibration for particle sizes 1 µm(c) and larger, sensor resolution and counting performance of liquid automatic particle counters that are capable of analysing bottle samples;

2. secondary particle-sizing calibration using suspensions verified with a primary calibrated APC;

3. establishing acceptable operation and performance limits;

4. verifying particle sensor performance using a test dust;

5. determining coincidence and flow rate limits.

This document is applicable for use with hydraulic fluids, aviation and diesel fuels, engine oil and other petroleum-based fluids. This document is not applicable to particle-sizing calibration using NIST SRM 2806b primary calibration suspensions.