A Filter is different than a Purifier

Berkey Purifier vs common water filter

There are two different classification standards for water treatment devices.

The first classification is a water filter, to meet this standard a water treatment device must remove at least 99.99% of pathogenic bacteria. This is known in the water filter industry as a log 4 reduction.

The second classification is a water purifier, to meet this standard a water treatment device must remove at least 99.9999% of pathogenic bacteria (log 6 reduction). In addition the water purifier must be capable of reducing viruses by at least 99.999% (log 5 reduction).

All Berkey systems that contain the Black Berkey elements are classified as water purifiers. In fact Berkey Water Purifiers remove 99.9999999% (log 9 reduction) of pathogenic bacteria. To our knowledge no other water filtration device in the world can match that claim.