How long must you immerse equipmemt and utensils in a non-chlorine sanitizing solution

A non-chlorine chemical such as iodine may be used as a sanitizing solution. To use iodine as a sanitizing solution, it should be around 12.5-25 ppm in water that is at least 75° F. Utensils and equipment must be immersed for only 30 seconds because it may lose its effectivity if the pH level gets too high due to high temperature. Discoloration may also result if the utensils and equipment are in prolonged contact with the solution.

a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.