The PURE FUEL System
Exceeds Engine Manufacturers Recommended
ISO 18/16/13 Cleanliness Target
ISO Fuel Requirements: The standard established by ISO (International Organization for Standardization) provides a common measurement system that engine and fuel system manufacturers use to designate acceptable particle levels in the fuel system. Determining fuel cleanliness requirements includes the measurement of both particle size and count. ISO 4406 utilizes a series of three numbers (18/16/13) to identify the particle count per milliliter at 4, 6 and 14 micron sizes. Engine manufacturers recommend ISO 18/16/13 or better as the cleanliness target in fuel tanks.
Using the table below, the ISO code number to the left is used to represent the number of particles per ml. For instance, a reported fluid sample with an ISO of 21 / 19 / 14 would mean that there are 10,000 to 20,000 ppm of particles larger than 4µm (ISO 21), 2,500 to 5,000 ppm of particles larger than 6µm (ISO 19), and 80 to 160 ppm of particles larger than 14µm (ISO 14).
How big is a Micron?
When talking about things in terms of “micron” measurements (µm), a micron is simply an abbreviation for a “micrometer”, or 1/1,000,000 of a meter. Being equal to roughly .00004 inches, a micron is not visible to the human eye (which is limited to about 40 microns).
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Microns are a standard unit of measurement in many sciences, industrial manufacturing, and other industries reliant on fine precision measurements.
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The diameter of a human hair, which can be clearly seen by the naked eye, is about 80 microns in diameter. A United States one-cent coin is 19,053 microns in diameter. White blood cells measure at about 25 microns, while bacteria range from a fraction of a micron to about 2 microns in diameter.
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It is important to note the ISO testing standards of measuring for 4µm / 6µm / 14µm, as all of these micron sizes are invisible to the human eye without the use of a microscope. These ISO numbers are extremely important to quantify considering mechanical equipment components, such as injectors with specific micron tolerances, or other small openings in pumps that are susceptible to mechanical wear driven by the presence of these microscopic particulates in the fuel.
