Barrel 03 : (BBL or bbl): A common unit of liquid volume measurement in the petroleum industry. One barrel (1bbl) is equivalent to 42 gallons (158.97 liters). (WLOP)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}