ORP is an acronym that stands for Oxidation Reduction Potential.

 

This is a direct measurement of the effectiveness of the sanitizer in your pool water. It is affected by the level of stabilizer in the pool water, the pH, Total Dissolved Solids, phosphates and the Total Alkalinity.

 

ORP does not have a linear relationship with the chlorine residual you would find by testing your pool water using a test kit . As an example, if your pH is very high, your sanitizer is also very high, and your chlorine is within the normally considered safe range, you would have ineffective chlorine because it is locked up in the stabilizer and pH.  If you were to reduce the stabilizer level and lower the pH, leave the chlorine residual alone, you would find that the ORP would increase.

 

ORP is typically used as a means to measure the sanitizer levels in a pool by automated chemical controllers.  These units measure the ORP by utilizing a probe immersed in a water sample from the pool that measures the current that passes through the water.

Tags: ORP, Oxidation Reduction Potential, sanitizer, pool chemicals