ISO 1171 (latest revision 2016) is an industry-adopted global standard and a common platform that defines the formal process and methodology for calibrating a liquid particle counter for the Fluid Power industry. Primary particle-sizing calibration is conducted using NIST SRM 2806 suspensions with particle size distribution certified by the United States’ National Institute of Standards and Technology (
NIST). A secondary calibration method with traceability to NIST uses suspensions of ISO MTD which are independently analyzed using an automated particle counter calibrated by the primary method.