Target ISO Cleanliness Selection Chart

How to Read ISO Cleanliness Codes

Know What Your Codes Mean

ISO cleanliness codes  help us understand the amounts and sizes of contaminating particles in fluids and set target goals when cleaning fluids. It is never realistic to believe we can or will completely remove all contaminates from a fluid. Instead, ISO codes can be used to set attainable goals with proven results.

ISO codes quantify contamination levels per milliliter of fluid at three distinct particle sizes: 4μ[c], 6μ[c], and 14μ[c]. When you are looking at an ISO code, you are looking at three measurements; the volume of particles in the fluid that are 4μ[c] in size and greater, the volume of particles 6μ[c] and greater, and the volume of particles 14μ[c] and greater.

Understanding ISO Codes

What is often the most confusing about ISO codes is that the ISO code number is a code that corresponds to a range, and is not a volume measurement itself. The chart below shows how ISO codes correspond to volume measurements. The important thing to remember is that for every 1 point increase in ISO code, there is a DOUBLING of the contaminate volume range. So, if you go from a code 19 to a code 20, you jump from a contaminate range of 2,500-5,000 particles per milliliter (p/ml) to a range of 5,000-10,000 p/ml.

ISO codes and corresponding particle volumes

Let’s take an ISO cleanliness code example and break down it’s meaning. Let’s say your fluid test comes back with an ISO code number that reads 23/21/20. That would mean you have particles 4μ[c] present in your fluids in the range of 40,000-80,000 p/ml, 6μ[c particles or larger present in volumes between 10,000-20,000 p/ml, and particles 14μ[c] or larger present in volumes of 5,000 -10,000p/ml.

How to Set Target ISO Cleanliness Codes

While every situation is different, we are often aiming for ISO code ranges that land somewhere between 12-17 for the first number, 10-14 on the second, and 8-13 for the third AFTER fluid reconditioning. If, in the example above, we could lower your numbers to 17/15/14, that would mean:

  • Dropping the volume for 4μ[c] from 40,000-80,000 particles to 640-1,300 p/ml
  • 6μ[c] count drop from 10,000-20,000 to 160-320 p/ml
  • 14μ[c] particles drop from 5,000-10,000 to 80-160 p/ml

That’s huge differences on all fronts! Imagine how much less wear and tear on your critical components that is. This is why fluid reconditioning helps extend the life of equipment and has many other benefits.

When we set goals for fluid reconditioning programs, we take several factors into consideration. Below is an example of a chart we might use to reference the following key factors and determine acceptable ISO codes and particle ranges to aim for.

Target ISO Cleanliness Selection ChartWhen using this chart, we are taking into account:

  1. Your main objectives for the cleaning program (minimizing repairs, extending equipment life, meeting regulations, satisfying warranties, etc)
  2. The most sensitive component coming into contact with the fluid, This component is the one we want to based the entire standard off of to make sure our fluid is optimized for that critical piece of equipment.
  3. The type of fluid used (petroleum or non-petroleum based fluids).
  4. The presence of additional factors, including:
    1. How critical the most sensitive component is to safety or overall system reliability
    2. Frequent cold starts
    3. Excessive shock or vibration
    4. Severe operating conditions

If you are interested in a competitive quote for your upcoming fluid conditioning, or you simple want to request a system evaluation, contact PetrolinkUSA today: 1-800-770-4510

Charts sourced from: How Important is the ISO Cleanliness Code in Machinery LubricationMachinery Lubrication Magazine