Is the ISO 4406 rating important?
Yes, it is very important!
The ISO 4406 rating tells us the cleanliness level of our lubricant. It tells us the number of particles that can pass through a 4, 6 and 14 micron rating.
However, the value on the ISO rating does not represent the number of particles. On the contrary, it represents the range in which the number of particles can lie.
One key point to remember is that the rating will always change from the time that the sample was taken to the date that the results were processed.
Therefore, it is a good idea to use the sample result as a guide as estimate a bit higher for the real value of your lubricant.
Check out our article which goes into more detail about ISO 4406.
Matt Spurlock CLS, CMRP, MLE explains further about redefining the ISO code in his article entitled; "A Twist on Particle Evaluation: Redefining the ISO Cleanliness Code".