NSF Standard 53 Test Protocol by an Independent Laboratory

20,000 gallons of city water, spiked with high levels of specific contaminants, was run through a KDF/GAC cartidge. The efficiency shown below was measured AFTER 20,000 gallons had passed through the cartridge (when new, removal is 99+%). Most other non-standard tests show results after only one pass of contaminated water, which does not indicate how the filter will perform towards the end of its life. To pass the NSF-53 protocol, the effluent must be under the EPA Maximum Contaminant Level (MCL) throughout the test.
All concentrations are measured in milligrams per liter (mg/l).

Test Results at 20,000 Gallons

Chemical Influent	Effluent	Efficiency	EPA	MCL
THM (chloroform)	0.57	0.029	95%	0.1
Lead	0.19	0.006	97%	0.025
Fluoride (1)	8.26	0.78	91%	1.4
Nitrate (1)	30.7	8.03	74%	10.0
Barium	10.4	0.56	95%	1.0
Arsenic	0.37	0.007	98%	0.05
Cadmium	0.03	0.004	87%	0.01
Chromium VI	0.15	0.011	93%	0.05
Chromium III	0.163	0.003	98%	0.05
Selenium	0.1	0.006	94%	0.01
Mercury	0.006	0.000*	99+%	0.002
Endrin	0.0008	0.000*	99%+	0.0002
Lindane	0.011	0.0012	89%	0.004
Methoxychlor	0.32	0.0059	98%	0.1
Toxaphene	0.013	0.000*	99%+	0.005
2,4-D	0.3	0.02	93%	0.1
Silvex (2,4,5-TP)	0.029	0.004	86%	0.01

: Notes:
* Below detectable limit.
(1) While this test shows a reduction in these contaminants, KDF is inconsistant in their removal in certain water conditions. We offer special nitrate and fluoride filters, or reverse osmosis, if removal is needed.

Chlorine removed from over 28,000 gallons

A separate test was run on another KDF/GAC cartridge to determine chlorine removal capacity. The challenge solution contained 3 mg/l chlorine (most cities use less than 1 mg/l). 2 mg/l lead was also added. At 20,000 gallons, both were still being removed at over 99.9% efficiency. The test was terminated at 28,400 gallons when the chlorine removal rate hit 90%. At that time, the lead removal was still 97.6%.