Thanks for the information; the device is a Rosemount 5600 series
The Rosemount 5600 uses state-of-the art microwave technology to get highest reliability and precision. It measures the level of liquids, slurries, and solids. The transmitter operates in a wide range of temperatures, pressures, vapor gas mixtures, and various process conditions. (We are already using the series in the tank field and it has been very reliable so far).
The plan is to perform the job under Fresh Air (full face supplied air w/ escape pack-protection for vapors), bunker gear (jacket, overalls, boots) protection from heat, Full body harness and tie off – protection from falling. I plan on using 2 cranes, (1) to station the new manway with device and all gaskets ready to install approximately 10ft from the workers and (1) crane to lift the old manway off the tank.
The N2 supply is on pressure control to the tank and an additional amount of N2 will be added to maintain a positive pressure and prevent air from entering the manway. I am working with the Safety & Fire dept to address any concerns.
Please advice on any Safety concerns or potential hazards.