Barrel

Wood barrels

Barrel is an old English word for a big holder of liquids, such as petrol, beer, wine or oil. Barrels are most commonly made of either wood or metal.

A barrel is also used to measure liquids. One barrel of oil is about 158.987 litres (42 US gallons). It is shortened as "b". This use may have come from the early Pennsylvanian oil fields where wooden barrels were used to store and move oil around. In 1866, the people of West Virginia started using it regularly. At this time, the amount was set to 42 gallons. It was later world-wide for measuring amounts of oil and pricing it.

Different sizes

The size of some standard barrels is not the same in all countries. Some countries have different sizes for different liquids.

• In the United Kingdom, there is a standard barrel for beer. It is 36 imperial gallons ( about 163 litres).
• In the United States, a standard barrel for liquids is 31.5 US gallons (about 119.2 litres). For beer, the standard barrel is 31 US gallons (117.3 litres), because of tax laws.