Indian Farmers Fertiliser Cooperative Ltd. (IFFCO) Phulpur unit is operating two large ammonia and urea complex. Ammonia is an intermediate product during the manufacturing of Urea. Although Ammonia is a hazardous chemical, but storage of ammonia is a necessity for smooth operation of Complex. Hence, considering that the safety is of utmost importance, the periodical inspection of storage facility is very important. Decommissioning and Recommissioning are pre- and post- activities of inspection of Ammonia Storage Tank. This article gives insight to various steps taken at Phulpur unit during De-commissioning, Inspection and Re-commissioning of one of the ammonia storage tanks. The inspection with help of various NDT techniques established the integrity of tank.