The common perception is that since atmospheric air is free, compressed air is also free. However, the cost of compressed air contributes to about 10% of the plant's total electricity costs, making it one of the most expensive utilities. With low efficiency compressed air systems, plants can lose up to 30% of its compressed air to leaks, yet little or no action is taken to fix this simply because there is no measurement. Free air delivery (FAD) measurement at the delivery end helps to reveal these losses so that corrective action can be taken, thereby reducing overall consumption and resulting in substantial savings.