Casual observers watching operators taking level measurements in storage tanks would mistakenly take it to be an unskilled and very simple job. However, it is not so seemingly simple and numerous errors could creep in easily vitiating the level readings and the precautions to minimize these. Even minor errors in level and temperature measurements seriously affect the results of the tank volume content calculations and cause sizable financial loss to either the seller or the purchaser as of millions and in petroleum business even billions of rupees transfer between parties on the basis of tank volume measurements.