Abstract: An odor control system neutralizes odors from any source such as those from a sewage disposal plant. The odor control system recirculates a brine solution containing NaOCl. This recirculated solution contacts the unwanted odors to neutralize them. Sufficient NaOCl is added electrochemically to the solution to neutralize the unwanted odors under normal operating conditions. When there are peak odor conditions the unwanted odors exceed the capacity of the electrochemically produced NaOCl. During such peak conditions, supplemental concentrated NaOCl is added from a storage tank. The concentration of the NaOCl in the soolution is determined by sensing the oxidation reduction potential (ORP) in the solution to produce an ORP signal. The ORP signal controls the concentration of NaOCl in the solution including that supplied electrochemically as well as that supplied from the storage tank.