Calculating the remaining amount of oil in a tank is derived from the tank's capacity, divided by the height of the tank and multiplied by its depth. Before making this calculation, the depth, height and capacity of the tank must be accurately measured.
Calculating the capacity of an oil tank requires measuring the unit. The length, width and height of the tank must be recorded for rectangular tanks. Multiply these figures by 0.0043 to produce the gallon size of a tank.
After producing the gallon size, determine how much oil is left by calculating the depth of the tank. To produce this figure, insert a tape measure until it hits the bottom of the tank. Slowly remove the tape measure and record the oil line. The end of the line reflects the number of inches or depth of the tank.
Next, determine the remaining amount of oil by dividing the tank's capacity by its height and multiplying the result by the depth of the tank.
The majority of oil tanks have gauges to reveal how much oil is remaining in the unit; however, if this feature is not available, there is a method to manually the check oil levels. The process of "sounding" is an effective way to determine current oil levels in a tank. Sounding requires a tape measure, writing utensil and calculator.