The Doulton ceramic filter is designed to trap bacteria mainly on the outer surface of the ceramic element preventing them from passing through into the drinking water. Given favorable temperature and pressure conditions, the accumulated bacteria could proliferate and grow unless prevented by some means. To prevent this our elements (except the Standard, Ceracarb and Ceramet) are manufactured with a small amount (about 0.07%) of silver in ceramic.
Silver is a recognized bactericide, so when the bacteria comes into contact with the silver impregnated ceramic, their growth is inhibited. More importantly, bacterial "grow-through" is eliminated. This self-sterilizing effect is known as the Bacteriostatic effect. The silver leach rate from the ceramic is very low and always well below the national recommended limits.
The Imperial Sterasyl ceramic filter cartridge has the same benefits as the regular Sterasyl, however, the roughly 1/3 larger diameter allows a significantly greater flow rate. At the present time, the Imperial Sterasyl is available only as a cartridge.
The Imperial Sterasyl cartridge is 2 3/4" O.D. by 9 3/4 long and is designed to fit a standard 10in "Slim Line" water filter housing.
Pathogenic Bacteria
Cholera, Typhoid, Salmonella, Serratia, E. Coli, fecal coliform - > 99.99% removal
Cysts
Cryptosporidium, Giardia Lamblia - 100% removal (based on tests by Arizona State University)
Sediment
Down to 0.9 micron absolute; 0.5 - 0.8 micron with a filter efficiency of
>99.99% (based on test performed by Spectrum
Laboratories, Minneapolis,MN)