ISO 11171 is an international standard for calibrating liquid
particle counter
A particle counter is used for monitoring and diagnosing particle contamination within specific clean media, including air, water and chemicals. Particle counters are used in a variety of applications in support of clean manufacturing practices, ...
s. As the functionality of
hydraulic fluid
A hydraulic fluid or hydraulic liquid is the medium by which power is transferred in hydraulic machinery. Common hydraulic fluids are based on mineral oil or water. Examples of equipment that might use hydraulic fluids are excavators and backhoe ...
s suffers when contaminated with particles, particle counters are used for contamination control. The particle counter determines the concentration and the size distribution of the particles. Therefore, the accuracy of the liquid particle counter has to be established through calibration.
According to ISO 11171 for the primary particle-sizing calibration
NIST
The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical sci ...
SRM 2806 suspension{{clarify, date=December 2013 has to be used. In annex "F" of ISO 11171, preparation of secondary calibration suspension is described.
In general ISO 11171 specifies procedures for two different subjects:
* sample preparation
* sensor calibration (particle-sizing calibration, coincidence error, resolution and
flow rate
Flow rate may refer to:
* Flow measurement, a quantification of bulk fluid movement
* Mass flow rate, the mass of a substance which passes per unit of time
* Volumetric flow rate, the volume of fluid which passes per unit time
** Discharge (hydrol ...
limit determination etc.)
Source document
* ISO 11171:2010(E) ''Hydraulic fluid power – Calibration of automatic particle counters for liquids'', ISO 2010
ISO standards, #11171