A Division of Arctic Refrigeration and Merchandise Inc.
312 S. Santa Fe Ave. Pueblo, Colorado. 81003 719-545-1800 Order line 1-800-360-2660
| HISTORY | ||||
Bacteria
The principle of our filter was originated by Sir Henry Doulton in 1854 when he introduced a
gravity earthenware filter to strain out bacteria from the river Thames which, at that time, was used
to supply drinking water. Thames river water was heavily contaminated with Cholera and
Typhoid; these diseases had reached epidemic proportions.
Bacteria are single-celled micro-organisms that feed on digestive wastes and dead tissue. Some
bacteria are beneficial but some can cause disease. Disease causing bacteria are called pathogenic
bacteria.
Since waterborne pathogenic bacteria (such as typhoid, cholera, and shigella) are greater than one
micron in size, they cannot pass through the Doulton ceramic filter. Moreover, during testing, the
concentration of bacteria fed to the filter is artificially high in order to simulate a challenging test for
the filter. The most aggressive "real life" condition 'would normally be at least 1000 times less
severe.
Nearly all drinking water contains ubiquitous bacteria that tend to multiply when retained in
conducive situations. While the Doulton ceramic retains pathogenic bacteria, smaller heterotrophic
bacteria do pass through. Since these heterotrophic bacteria are harmless, normally there are no
problems.
However, if normal use of the filter is interrupted by holidays or vacations, growth of these
bacteria may result in a 'flat' or 'stale taste for a period of time when use of the filter resumes. This
is especially true for the filter elements that contain activated carbon such as the Super Sterasyl
(contains granulated activated carbon). This problem may be eliminated by flushing the filter
system for several minutes after any prolonged period of inactivity.
BACTERIAL MITOSIS AND "GROW-THROUGH"
Mitosis is the name for the usual method of bacterial cell division. This division is characterized by
resolving the chromatin of the cell nucleus into a threadlike form that condenses into
chromosomes, each of which separates longitudinally into two parts, one part of each
chromosome being retained in each of the two new daughter cells.
When conditions of growth (cell division) are right (proper environmental conditions , temperature,
pressure, etc.) and sufficient nutrients, the "threadlike forms" can penetrate the ceramic structure of
other ceramic shells and create bacterial cells on the inside of the element.
Sterasyl grade filter elements incorporate pure silver into the porous ceramic shell to prevent
"grow-through" from occurring.