How to calculate an Intrinsically Safe loop approval

How to calculate an Intrinsically Safe loop approval including the impact of using Ex ic (Zone 2) and gas group on cable lengths. Revised & updated Dec 2020

We all know what can happen when the correct techniques are not used when interfacing into the Hazardous Area. Using Intrinsic Safety (Ex i based on IEC/ SANS 60079-11; IEC/ SANS 60079-25), the energy in the hazardous area is limited to below the ignition energy of the gas present, thereby preventing explosions.