The majority of bunker fuel is delivered to ships by barge. Trapped air, held in suspension within viscous bunker oil, artificially increases its volume. This effect has been a major and hitherto unsolvable problem for the shipping industry. The measurement of the supplied quantity currently involves dipping barge tanks before and after delivery and undertaking various calculations and corrections to convert the tank volume measurement into a delivered mass. This process is fraught with difficulties, errors and personnel hazards. BP, recognizing all these problems, has embarked upon an ambitious project to utilize best available and economically viable technology to overcome the traditional quantity verification methods.