Imperial Fluid Ounces to Oil Barrels (fl oz (UK) to bbl)

1 imperial fluid ounce equals 0.0001787127865 oil barrels (rounded).

1 imperial fluid ounce = 0.0001787127865 oil barrels

How to convert imperial fluid ounces to oil barrels

To convert imperial fluid ounces to oil barrels, multiply the number of imperial fluid ounces by 0.0001787127865. The factor is rounded to 10 significant digits. To go the other way, multiply oil barrels by 5,595.570521 (rounded).

oil barrels = imperial fluid ounces × 0.0001787127865

Example: 10 imperial fluid ounces = 0.001787127865 oil barrels.

Pints, quarts, gallons and fluid ounces differ between the US and the UK. Units are labeled 'US' or 'imperial' to avoid confusion.

About these units

Imperial Fluid Ounce (fl oz (UK))

Imperial (British)Current unit

Exactly 28.4130625 mL. About 4% smaller than the US fluid ounce.

Imperial fluid ounce comes from the 1824 reform that defined the British gallon as the volume of ten pounds of water. Because a gallon was set at 160 fluid ounces, an ounce of water weighs about one ounce of mass, around 28.35 grams. That neat link between volume and weight was the point of the imperial scheme, and it explains why people long thought of fluid ounces and weight ounces as nearly the same.

Today an imperial fluid ounce is exactly 28.4130625 milliliters, one twentieth of an imperial pint. That is about 4 percent smaller than the US fluid ounce at 29.57 mL, so a US recipe using fluid ounces does not map one-for-one onto a British one. UK trade rules restricted its use in 1995, and it lives on mostly on older labels, in bars and in recipes. Twenty of them fill an imperial pint, which makes the pint the easiest way to picture one.

1 imperial fluid ounce = 0.0284130625 liters (exactly).

Sources: Wikipedia: Fluid ounce; UK Weights and Measures Act 1985, Schedule 1

Oil Barrel (bbl)

US customaryCurrent unit

Exactly 42 US gallons (158.987 L). The unit of crude oil trade since the 1860s Pennsylvania oil fields.

The oil barrel did not come from the oil industry's own design but from the barrels already lying around Pennsylvania. After Drake's well of 1859 started a boom, producers shipped crude in whatever containers were handy: whiskey barrels of around 40 gallons, plus 42 and 45 gallon casks. Buyers grew suspicious of the inconsistency, and around 1866 producers settled on the wine tierce of 42 gallons, two gallons bigger than the common whiskey barrel. An Oil City circular of August 1866 also promised an allowance of two gallons in every 40.

By 1872 the 42-gallon standard was firmly established, and US government bodies adopted it in 1882. The barrel is exactly 42 US gallons, about 159 liters, and remains the worldwide pricing unit for crude, even though many countries report volumes in cubic meters. EIA says Strait of Hormuz flows of 20 million barrels a day equal about a fifth of global consumption, implying roughly 100 million barrels a day. The abbreviation bbl has a disputed origin: a popular story links it to Standard Oil's blue barrels, but the abbreviation predates the oil industry.

1 oil barrel = 158.9872949 liters (approximately).

Sources: Wikipedia: Barrel (unit); NIST SP 811, Appendix B.8: conversion factors for volume; EIA: Today in Energy, Strait of Hormuz oil flows

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