Black Berkey filter pore size

Berkey Filter Pore Size

Black Berkey filter pore size

A frequently asked question by the geek-type might be “What’s the Berkey filter pore size?”

The Berkey filter’s micro fine pores are incredibly small. They prevent micro fine particulate such as bacteria, virus and even food coloring particulate from passing through. It’s a “tortuous path” for the contaminants.

The micro fine pores trap contaminates and lets H20 (water) molecules through.

The current Black Berkey filter elements are a proprietary formulation.

Logically, you might wonder the following… If the pores are so small, won’t it clog really quickly? Berkey says this:

“The proprietary filter formulation used in Black Berkey® purification elements makes up for the incredibly small pore size by utilizing an exponentially greater number of micro pores in each purification element than that found in other filter elements.”

“This is the reason Black Berkey® purification elements produce approximately 8 times more water per hour than do other elements.”

Therefore, while some of the surface pores will clog up from contaminates, it is difficult for such contamination to overwhelm all of the pores and clog up the filter.

What’s The Size Of The Berkey Filter Pores?

They don’t reveal it directly. Probably because of their proprietary method. However I was able to get a pretty good clue…

Virus is much smaller than bacteria. And evidently they test for something called the ” MS2 and Fr Coliphage”. What’s that? (you might ask)…

These virus were selected, by both the EPA and the Military, because of their small size relative to other virus strains and the difficulty in removing both strains. They each are approximates 24-26 nanometers in size which makes them among the smallest of virus.

Berkey states, “Black Berkey® purification elements have been tested to remove viruses to greater than the EPA purification standards .”

Therefore one could conclude that their pore size is apparently at least (less than) 24 nanometers.

University of Utah Cell Size and Scale Chart

You have to check this out! It’s mind-blowing…

This will help you understand the stunning difference in cell sizes and the scale thereof.

Click the image below (it will take you to a genetics page at University of Utah) and slide the scale at the bottom to visualize the size of virus vs bacteria vs other potential contaminates and magnify to greater levels.

The Takeaway

As I’ve said a thousand times, The Berkey Water Purification System is among the best there is. I found it interesting to discover a bit about their filter pore size. Maybe you did too.

Considering the purchase of a Berkey Filter system? Then get yours from Jeff (The Berkey Guy) over at He is authorized by Berkey in the United States and offers lifetime warranty.

Why “The Berkey Guy”?

Tip: Use the SEARCH function (in the MENU) and type in Berkey to discover the many articles written on the subject.


    1. If/when you do order, like I said in the article I recommend getting them from “The Berkey Guy”. And if you do, let him know that you saw it from Modern Survival Blog ;)

      He was one of my first sponsors way back in the early days of MSB nearly a decade ago. It’s reassuring to purchase from a business that has longevity. Plus, you’re supporting a family business here in the USA.

  1. I am filtering the water stored in (20) 30 gallon drums the summer of 2011, and selling the drums.
    You think it will be an easy job, get done quickly, but I’m still on the first drum.
    I guess I use less water per day than most families. I’m alone all day, cook only dinner, and use filtered water for tea and coffee I drink.

    1. JJ

      Are you close by? I’d like to get some drums. Am out on Oly Pen.

      1. Anony Mee I just checked Craigslist Olympic Peninsula and found several 55 gallon water barrels for sale out your way.

        Thought you’d like to know. I sort of miss Port Townsend WA a great place to grow up with Ft Warden and all that.

        1. Thank you, me2, very much.

          Hoping JJ gets in touch as would rather spend my cash with an MSB family member than not.

          Will keep your suggestion as alt1.

  2. Great article Ken. I have often wondered about the pore size of a Berkey filter. For comparison, the pore size in a reverse osmosis membrane filter is about 0.5 nanometers. Still for a non pressured, easy to use system, the Berkey is impressive.

  3. Great article Ken
    The university of Utah really put things into prospective for a common person like myself.

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