This International Standard specifies the code to be used in defining the quantity of solid particles in the fluid used in a given hydraulic fluid power system.
BS ISO 4406:2000 history
2021BS ISO 4406:2021 Hydraulic fluid power. Fluids. Method for coding the level of contamination by solid particles
2017BS ISO 4406:2017 Hydraulic fluid power. Fluids. Method for coding the level of contamination by solid particles
2000BS ISO 4406:1999 Hydraulic fluid power - Fluids - Method for coding the level of contamination by solid particles