The tester reports free available chlorine by measuring oxidation reduction potential cross referenced with pH
Ultrapen PT4  is Myron L Co.’s new pocket tester for measuring free chlorine disinfecting power, free chlorine equivalent (FCE) and temperature. It is waterproof and designed to be accurate, fast and simple to use in diverse water quality applications.
The Myron L Co. FCE function reports free available chlorine (FAC) quickly and accurately by measuring oxidation reduction potential, the chemical characteristic of chlorine that directly reflects its effectivity, cross referenced with pH. Both DPD kits and colorimeters may tell the user the FAC value of the sample in the test tube, but because the chemistry of that sample is quite different from the source water being analyzed, the results are imprecisely related to actual disinfection power. The Myron L Co.  FCE function measures the real, unaltered chemistry of source water, including moment-to-moment changes in that chemistry.
Features of the Ultrapen PT4  include:
- • Accuracy of up to ±0.3 ppm FCE;
- • Proprietary sensor design;
- • Calibration with pH and ORP standard solutions;
- • Automatic temperature compensation;
- • Temperature readout;
- • Waterproof; and
- • Powered by one N type battery (included).