How to measure ORP?
ORP (Oxidation Reduction Potential) is measured with an ORP Meter or ORP Electrode. ORP measurement is displayed in Millivolt. ORP Meters and ORP Electrodes are special instruments designed to measure the strength of the oxidation process in the water.
Explaining ORP completely can be a bit difficult as it involves a very complex chemical process that is depended on a million different variables. Most people known ORP because the have a pool with an automated dosing system or they use their ORP tester to measure the chlorine in their pool. Actually an ORP meter or ORP electrode does not measure the actual chlorine level in a pool, but it does measure the disinfectant power of water. The higher the ORP level in your pool, the more disinfectant power it has.
Remember to calibrate your ORP Meter and ORP Electrdoe regurlarly with ORP Calibration Buffer