5 min read

[Video] How Big is a Micron?

Mon, Aug. 26, 2013

If you’ve been following our blog, you probably have a pretty solid understanding of ISO fluid cleanliness codes (if not, click here). You know that ISO codes quantify levels of particulate contamination at three different micron sizes (4μm/6μm/14μm), but how big is a 4μm particle? Watch the video below for a brief explanation of micron size.


Video Transcript

Hi, thanks for taking the time to watch this video. Today I want to talk to you about how particles of dirt that are so small we can’t even see them with our eyes can wreak havoc on our systems.

In our previous video, we talked about ISO fluid cleanliness codes, which are a measurement of particles per milliliter of dirt at three different micron sizes; those micron sizes being 4, 6 and 14. But how big is a particle that’s 14 microns in size? Most people don’t really know so that’s the understanding we’re going to try to develop today.

Our first example is a grain of salt, which comes in at about 100 microns. If you put a grain of salt on your finger, your eye picks it up pretty easily. If you move your finger farther from your face, your eye can still see it. It’s not that hard for your eye to pick up something that is 100 microns across.

The next example we’re going to talk about is the average human hair. The diameter of that is about 74 microns, so it’s smaller but it’s still visible. You may not be able to see it from as great of a distance but your eye can still pick it up. 

After we drop below the 40 micron range, our eye’s gonna need assistance in picking up any of the other examples. We’re going to have to have a microscope or something like that to see them. 

A white blood cell is about 25 microns in diameter and our next example, a red blood cell, is about 8 microns. And bacteria are at about 2 microns. 

The interesting thing to note when you’re taking this all in is that the largest particle that our ISO codes are measuring are 14 microns in size which is smaller than a white blood cell and much smaller than what our eye can pick up on its own. The reason that is is because it’s those very small particles that have the ability to get into the very small openings in our pumps, valves and bearings and cause mechanical wear, premature component failure and then loss of reliability and downtime.

We hope this will give you a better understanding of what you’re looking at or talking about the next time you interact with ISO codes. As always, if you have any questions please write us at info@hyprofiltration.com.

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Written by Brad Bainbridge


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