The need for real time operational technology poses a potential security challenge for devices such as Programmable Logic Controllers (PLC). This is generally because conventional security solutions like encryption are not able to be undertaken within a sensible short time frame. This work implements a potential solution proposed which could be applied in real time following a standard set out in IEC 61131-3. This would be a security function which would be vendor independent. The work was then tested on a system utilizing openPLC running on a Raspberry Pi 4 model B with the ESP32 chip providing the processing of input/output validation allowing for the solution to undergo a successful proof of concept.