View source for Gasoline

{{Short description|Liquid fuel derived from petroleum}}
{{Redirect|Petrol|other uses|Petrol (disambiguation)|and|Gasoline (disambiguation)}}
{{Use dmy dates|date=February 2020}}
{{Use American English|date=April 2016}}
[[File:Gasoline in mason jar.jpg|thumb|Gasoline in a glass jar]]

'''Gasoline''' ([[North American English]]) or '''petrol''' ([[English in the Commonwealth of Nations|Commonwealth English]]) is a [[petrochemical]] product characterized as a transparent, yellowish, and [[flammable liquid]] normally used as a [[fuel]] for spark-ignited [[internal combustion engine]]s. When formulated as a fuel for [[petrol engine|engine]]s, gasoline is chemically composed of [[organic compound]]s derived from the [[fractional distillation]] of [[petroleum]] and later chemically enhanced with [[gasoline additive]]s. It is a high-volume profitable product produced in crude oil refineries.<ref>{{Cite book |last1=Gary |first1=James H. |title=Petroleum refining: technology and economics |last2=Handwerk |first2=Glenn E. |date=2001 |publisher=Dekker |isbn=978-0-8247-0482-7 |edition=4. |location=New York Basel |page=1}}</ref>

The ability of a particular gasoline blend to resist premature ignition (which causes [[Engine knocking|knocking]] and reduces efficiency in [[reciprocating engines]]) is measured by its [[octane rating]]. [[Tetraethyl lead]] was once widely used to increase the octane rating but is not used in modern automotive gasoline due to the [[Lead poisoning#Gasoline|health hazard]]. Aviation, off-road motor vehicles, and [[racing car]] engines still use leaded gasolines.<ref>{{Cite web |title=Why small planes still use leaded fuel decades after phase-out in cars |url=https://www.nbcnews.com/business/business-news/leaded-gas-was-phased-out-25-years-ago-why-are-n1264970 |url-status=live |archive-url=https://web.archive.org/web/20210602213708/https://www.nbcnews.com/business/business-news/leaded-gas-was-phased-out-25-years-ago-why-are-n1264970 |archive-date=2 June 2021 |access-date=2 June 2021 |publisher=NBC News|date=22 April 2021 }}</ref><ref>{{Cite web |title=Race Fuel 101: Lead and Leaded Racing Fuels |url=https://www.sunocoracefuels.com/tech-article/race-fuel-101-lead-leaded-racing-fuels |url-status=live |archive-url=https://web.archive.org/web/20201025013618/https://www.sunocoracefuels.com/tech-article/race-fuel-101-lead-leaded-racing-fuels |archive-date=25 October 2020 |access-date=July 30, 2020}}</ref> Other substances are frequently added to gasoline to improve chemical stability and performance characteristics, control corrosion, and provide fuel system cleaning. Gasoline may contain oxygen-containing chemicals such as [[ethanol]], [[MTBE]], or [[ETBE]] to improve [[combustion]].

==History and etymology==
{{main|History of gasoline|l1=History and etymology of gasoline}}
English dictionaries show that the term ''gasoline'' originates from ''[[Fuel gas|gas]]'' plus the chemical suffixes ''[[wikt:-ole|-ole]]'' and ''[[wikt:-ine|-ine]]''.<ref>{{Cite Merriam-Webster|gasoline}}</ref><ref>{{Cite Dictionary.com|gasoline}}</ref><ref>[https://www.oed.com/dictionary/gasoline_n?tab=factsheet#3253102 gasoline]". ''Oxford English Dictionary''. Oxford University Press, 2024.</ref> ''Petrol'' derives from the [[Medieval Latin]] word ''petroleum'' (L. ''petra'', rock + ''oleum'', oil).<ref>{{Cite encyclopedia |publisher=HarperCollins |dictionary=The American Heritage Dictionary |title=petroleum |url=https://www.ahdictionary.com/word/search.html?q=petroleum |access-date=2024-05-26 |archive-date=16 May 2020 |archive-url=https://web.archive.org/web/20200516164428/https://www.ahdictionary.com/word/search.html?q=petroleum |url-status=live }}</ref>

Interest in gasoline-like fuels started with the invention of internal combustion engines suitable for use in transportation applications. The so-called [[Otto engine]]s were developed in Germany during the last quarter of the 19th century. The fuel for these early engines was a relatively volatile [[hydrocarbon]] obtained from [[coal gas]]. With a [[boiling point]] near {{convert|85|C|F}} ([[N-octane|''n''-octane]] boils at {{convert|125.62|C|F}}<ref name="CAS 111-65-9">{{cite web |url=https://cameochemicals.noaa.gov/chemical/1240 |title=N-OCTANE / CAMEO Chemicals / NOAA |publisher=National Oceanic and Atmospheric Administration |archiveurl=https://web.archive.org/web/20230824074456/https://cameochemicals.noaa.gov/chemical/1240 |archivedate=24 August 2023 |accessdate=2023-11-06 |url-status=live }}</ref>), it was well suited for early [[carburetor]]s (evaporators). The development of a "spray nozzle" carburetor enabled the use of less volatile fuels. Further improvements in engine efficiency were attempted at higher [[compression ratio]]s, but early attempts were blocked by the premature explosion of fuel, known as [[Engine knocking|knocking]]. In 1891, the [[Shukhov cracking process]] became the world's first commercial method to break down heavier hydrocarbons in crude oil to increase the percentage of lighter products compared to simple distillation.

==Chemical analysis and production==
[[File:GasolineComp.png|right|thumb|Some of the components of gasoline: [[isooctane]], [[butane]], 3-[[ethyltoluene]], and the octane enhancer [[MTBE]]]]
[[File:Nodding_donkey.jpg|thumb|A [[pumpjack]] in the United States]]
[[File:Gulf_Offshore_Platform.jpg|thumb|An [[oil rig]] in the [[Gulf of Mexico]]]]
Commercial gasoline, as well as other liquid transportation fuels, are complex mixtures of hydrocarbons.<ref>{{Cite web |title=Hydrocarbon Gas Liquids Explained - U.S. Energy Information Administration (EIA) |url=https://www.eia.gov/energyexplained/hydrocarbon-gas-liquids/ |access-date=2022-08-05 |website=www.eia.gov |archive-date=5 August 2022 |archive-url=https://web.archive.org/web/20220805213231/https://www.eia.gov/energyexplained/hydrocarbon-gas-liquids/ |url-status=live }}</ref> The performance specification also varies with season, requiring less volatile blends during summer, in order to minimize evaporative losses.

Gasoline is produced in [[Oil refinery|oil refineries]]. Roughly {{convert|19|U.S.gal|L|sp=us|order=flip}} of gasoline is derived from a {{convert|42|U.S.gal|L|sp=us|adj=on|order=flip}} barrel of [[crude oil]].<ref>{{cite web |author=<!--Not stated--> |date=12 August 2016 |title=Gasoline—a petroleum product |url=https://www.eia.gov/energyexplained/index.cfm?page=gasoline_home |url-status=live |archive-url=https://web.archive.org/web/20170524145355/https://www.eia.gov/Energyexplained/index.cfm?page=gasoline_home |archive-date=24 May 2017 |access-date=15 May 2017 |website=U.S. Energy Information Administration website |publisher=U.S. Energy Information Administration |df=dmy-all}}</ref> Material separated from crude oil via [[distillation]], called virgin or straight-run gasoline, does not meet specifications for modern engines (particularly the [[octane rating]]; see below), but can be pooled to the gasoline blend.

The bulk of a typical gasoline consists of a homogeneous mixture of [[hydrocarbon]]s with between four and twelve [[carbon]] atoms per molecule (commonly referred to as C4–C12).<ref name="Ullmann2">Werner Dabelstein, Arno Reglitzky, Andrea Schütze and Klaus Reders "Automotive Fuels" in ''Ullmann's Encyclopedia of Industrial Chemistry'' 2007, Wiley-VCH, Weinheim. {{doi|10.1002/14356007.a16_719.pub2}}</ref> It is a mixture of paraffins ([[alkane]]s), olefins ([[alkene]]s), napthenes ([[cycloalkane]]s), and [[aromatic]]s. The use of the term ''paraffin'' in place of the standard chemical nomenclature ''alkane'' is particular to the oil industry (which relies extensively on jargon). The composition of a gasoline depends upon:
* the oil refinery that makes the gasoline, as not all refineries have the same set of processing units;
* the [[crude oil]] feed used by the refinery;
* the grade of gasoline sought (in particular, the octane rating).

The various refinery streams blended to make gasoline have different characteristics. Some important streams include the following:
* '''Straight-run gasoline''', sometimes referred to as ''[[naphtha]] (and also light straight run naphtha "LSR" and light virgin naphtha "LVN")'', is distilled directly from crude oil. Once the leading source of fuel, naphtha's low octane rating required organometallic fuel additives (primarily [[tetraethyllead]]) prior to their phaseout from the gasoline pool which started in 1975 in the United States.<ref>{{Cite web |last=Hofverberg |first=Elin |date=2022-04-14 |title=The History of the Elimination of Leaded Gasoline {{!}} In Custodia Legis |url=https://blogs.loc.gov/law/2022/04/the-history-of-the-elimination-of-leaded-gasoline/ |access-date=2025-01-16 |website=The Library of Congress}}</ref> Straight run naphtha is typically low in aromatics (depending on the grade of the crude oil stream) and contains some cycloalkanes (naphthenes) and no olefins (alkenes). Between 0 and 20 percent of this stream is pooled into the finished gasoline because the quantity of this fraction in the crude is less than fuel demand and the fraction's [[Octane rating#Research Octane Number (RON)|Research Octane Number]] (RON) is too low. The chemical properties (namely RON and [[Reid vapor pressure]] (RVP)) of the straight-run gasoline can be improved through [[Catalytic reforming|reforming]] and [[Isomerisation|isomerization]]. However, before feeding those units, the naphtha needs to be split into light and heavy naphtha. Straight-run gasoline can also be used as a feedstock for steam-crackers to produce olefins.
* '''Reformate''', produced from straight run gasoline in a [[catalytic reformer]], has a high octane rating with high aromatic content and relatively low olefin content. Most of the [[benzene]], [[toluene]], and [[xylene]] (the so-called [[BTX (chemistry)|BTX]] hydrocarbons) are more valuable as chemical feedstocks and are thus removed to some extent. Also the BTX content is regulated.
* '''Catalytic cracked gasoline''', or catalytic cracked [[Petroleum naphtha|naphtha]], produced with a [[Fluid catalytic cracking|catalytic cracker]], has a moderate octane rating, high olefin content, and moderate aromatic content.
* '''Hydrocrackate''' (heavy, mid, and light), produced with a [[hydrocracker]], has a medium to low octane rating and moderate aromatic levels.
* '''Alkylate''' is produced in an [[alkylation]] unit, using [[isobutane]] and C3-/C4-olefins as feedstocks. Finished alkylate contains no aromatics or olefins and has a high MON ([[Motor octane number|Motor Octane Number]]) Alkylate was used during world war 2 in [[aviation fuel]].<ref>{{cite web |date=6 August 2021 |title=Alkylate: Understanding a Key Component of Cleaner Gasoline |website=[[American Fuel and Petrochemical Manufacturers]] |url=https://afpm.org/newsroom/blog/alkylate-understanding-key-component-cleaner-gasoline |access-date=21 October 2024 }}</ref> Since the late 1980s, it is sold as a specialty fuel for (handheld) gardening and forestry tools with a combustion engine.<ref>{{cite web |title=Specially designed fuel for cleaner oceans |website=AlkylateFuel.com |url=https://www.alkylatefuel.com/ |access-date=21 October 2024 }}</ref><ref>{{cite web |title=The story behind Aspen Alkylate Fuel |website=AspenFuel.co.uk |date=5 June 2024 |url=https://aspenfuel.co.uk/about-aspen/#story |access-date=21 October 2024 }}</ref> 
* '''Isomerate''' is obtained by isomerizing low-octane straight-run gasoline into iso-paraffins (non-chain alkanes, such as [[isooctane]]). Isomerate has a medium RON and MON, but no aromatics or olefins.
* '''Butane''' is usually blended in the gasoline pool, although the quantity of this stream is limited by the RVP specification.
* '''[[Oxygenate]]s''' (more specifically [[Alcohol (chemistry)|alcohols]] and [[ester]]s) are mostly blended into the pool in the US as [[Ethanol fuel|ethanol]]. In Europe and other countries, the blends can contain [[Ethanol fuel|ethanol]] in addition to [[Methyl tert-butyl ether|Methyl tertiary-butyl ether]] (MTBE) and [[Ethyl tert-butyl ether]] (ETBE). MTBE in the United States was banned by most states in the early-to-mid-2000s.<ref>{{Cite web |last=US EPA |date=June 2004 |title=State Actions Banning MTBE (Statewide) |url=https://archive.epa.gov/mtbe/web/pdf/420b04009.pdf |website=EPA Archives}}</ref> A few countries still allow [[methanol]] as well to be blended directly into gasoline, especially in China.<ref>{{Cite web |title=China’s use of methanol in liquid fuels has grown rapidly since 2000 - U.S. Energy Information Administration (EIA) |url=https://www.eia.gov/todayinenergy/detail.php?id=30072 |access-date=2025-02-13 |website=www.eia.gov}}</ref> More about oxygenates and blending is covered further in this article.

The terms above are the jargon used in the oil industry, and the terminology varies.

Currently, many countries set limits on gasoline [[aromatic]]s in general, benzene in particular, and olefin (alkene) content. Such regulations have led to an increasing preference for alkane isomers, such as isomerate or alkylate, as their octane rating is higher than n-alkanes. In the European Union, the benzene limit is set at one percent by volume for all grades of automotive gasoline. This is usually achieved by avoiding feeding C6, in particular [[cyclohexane]], to the reformer unit, where it would be converted to benzene. Therefore, only (desulfurized) heavy virgin naphtha (HVN) is fed to the reformer unit<ref name="hedl2">{{cite journal |last1=Huess Hedlund |first1=Frank |last2=Boier Pedersena |first2=Jan |last3=Sinc |first3=Gürkan |last4=Garde |first4=Frits G. |last5=Kragha |first5=Eva K. |last6=Frutiger |first6=Jérôme |date=February 2019 |title=Puncture of an import gasoline pipeline—Spray effects may evaporate more fuel than a Buncefield-type tank overfill event |url=https://backend.orbit.dtu.dk/ws/files/160875647/1_s2.0_S0957582018306153_main.pdf |url-status=live |journal=Process Safety and Environmental Protection |volume=122 |pages=33–47 |doi=10.1016/j.psep.2018.11.007 |bibcode=2019PSEP..122...33H |archive-url=https://web.archive.org/web/20211102115932/https://backend.orbit.dtu.dk/ws/files/160875647/1_s2.0_S0957582018306153_main.pdf |archive-date=2 November 2021 |access-date=18 September 2021}}</ref>

Gasoline can also contain other [[organic compound]]s, such as [[organic ether]]s (deliberately added), plus small levels of contaminants, in particular [[organosulfur]] compounds (which are usually removed at the refinery).

On average, U.S. petroleum refineries produce about 19 to 20 gallons of gasoline, 11 to 13 gallons of distillate fuel [[diesel fuel]] and 3 to 4 gallons of [[jet fuel]] from each {{convert|42|USgal|liter|abbr=off|sp=us}} [[Oil barrel|barrel]] of [[Petroleum|crude oil.]] The product ratio depends upon the processing in an [[oil refinery]] and the [[crude oil assay]].<ref>{{cite web | url=https://www.eia.gov/energyexplained/oil-and-petroleum-products/refining-crude-oil.php | title=Refining crude oil—U.S. Energy Information Administration (EIA) | access-date=27 August 2022 | archive-date=27 August 2022 | archive-url=https://web.archive.org/web/20220827005655/https://www.eia.gov/energyexplained/oil-and-petroleum-products/refining-crude-oil.php | url-status=live }}</ref>

==Physical properties==
[[File:GasStationHiroshima.jpg|thumb|A [[Royal Dutch Shell|Shell]] [[Gasoline station|station]] in [[Hiroshima]], [[Japan]]]]

===Density===
The [[specific gravity]] of gasoline ranges from 0.71 to 0.77,<ref>{{cite web |author=Bell Fuels |title=Lead-Free gasoline Material Safety Data Sheet |url=http://www.sefsc.noaa.gov/HTMLdocs/Gasoline.htm |url-status=dead |archive-url=https://web.archive.org/web/20020820074636/http://www.sefsc.noaa.gov/HTMLdocs/Gasoline.htm |archive-date=20 August 2002 |publisher=[[NOAA]]}}</ref> with higher densities having a greater volume fraction of aromatics.<ref>{{cite book |last=Demirel |first=Yaşar |url=https://books.google.com/books?id=TsY8gJP7b58C&pg=PA33 |title=Energy: Production, Conversion, Storage, Conservation, and Coupling |date=26 January 2012 |publisher=Springer Science & Business Media |isbn=978-1-4471-2371-2 |page=33 |access-date=31 March 2020 |archive-url=https://web.archive.org/web/20200728070621/https://books.google.com/books?id=TsY8gJP7b58C&pg=PA33 |archive-date=28 July 2020 |url-status=live}}</ref> Finished marketable gasoline is traded (in Europe) with a standard reference of {{Convert|0.755|kg/L|lb/U.S.gal|abbr=|sp=us}}, (7,5668 lb/ imp gal) its price is escalated or de-escalated according to its actual density.{{clarify|reason=Denser gasoline is more expensive or less expensive?|date=May 2019}} Because of its low density, gasoline floats on water, and therefore water cannot generally be used to extinguish a gasoline fire unless applied in a fine mist.

===Stability <span class="anchor" id="Stability"></span>===
{{More citations needed|section|date=November 2022}}

Quality gasoline should be [[Shelf life|stable]] for six months if stored properly, but can degrade over time.<ref name=Stable>{{cite journal |title= It’s True: Gasoline Has an Expiration Date |first= Matt |last= Crisara |date= March 6, 2023 |journal= [[Popular Mechanics]] |url= https://www.popularmechanics.com/cars/a43168378/gas-has-an-expiration-date/ |access-date= March 14, 2025 |archive-url= https://web.archive.org/web/20250115025634/https://www.popularmechanics.com/cars/a43168378/gas-has-an-expiration-date/ |archive-date= January 15, 2025 |url-status= live |url-access= subscription}}</ref> Gasoline stored for a year will most likely be able to be burned in an internal combustion engine without too much trouble.<ref name=Stable/> <!-- UNSOURCED SINCE NOV 2022 However, the effects of long-term storage will become more noticeable with each passing month until a time comes when the gasoline should be diluted with ever-increasing amounts of freshly made fuel so that the older gasoline may be used up. If left undiluted, improper operation will occur and this may include engine damage from misfiring or the lack of proper action of the fuel within a [[fuel injection]] system and from an onboard computer attempting to compensate (if applicable to the vehicle).--> Gasoline should ideally be stored in an airtight container (to prevent [[oxidation]] or water vapor mixing in with the gas) that can withstand the [[vapor pressure]] of the gasoline without venting (to prevent the loss of the more volatile fractions) at a stable cool temperature (to reduce the excess pressure from liquid expansion and to reduce the rate of any decomposition reactions). When gasoline is not stored correctly, gums and solids may result, which can corrode system components and accumulate on wet surfaces, resulting in a condition called "stale fuel". Gasoline containing ethanol is especially subject to absorbing atmospheric moisture, then forming gums, solids, or two phases (a hydrocarbon phase floating on top of a water-alcohol phase).<ref name=Stable/>

The presence of these degradation products in the fuel tank or fuel lines plus a carburetor or fuel injection components makes it harder to start the engine or causes reduced engine performance <ref>{{cite journal |first1=Florian |last1=Pradelle |first2=Sergio L. |last2=Braga |first3=Ana Rosa F. A. |last3=Martins |first4=Franck |last4=Turkovics |first5=Renata N. C. |last5=Pradelle |date=November 3, 2015 |title=Gum Formation in Gasoline and Its Blends: A Review |journal=Energy & Fuels |volume=29 |issue=12 |pages=7753–7770 |doi=10.1021/acs.energyfuels.5b01894 }}</ref> On resumption of regular engine use, the buildup may or may not be eventually cleaned out by the flow of fresh gasoline. The addition of a fuel stabilizer to gasoline can extend the life of fuel that is not or cannot be stored properly, though removal of all fuel from a fuel system is the only real solution to the problem of long-term storage of an engine or a machine or vehicle. Typical fuel stabilizers are proprietary mixtures containing [[mineral spirits]], [[isopropyl alcohol]], [[1,2,4-trimethylbenzene]] or [[Gasoline additive|other additives]]. Fuel stabilizers are commonly used for small engines, such as lawnmower and tractor engines, especially when their use is sporadic or seasonal (little to no use for one or more seasons of the year). Users have been advised to keep gasoline containers more than half full and properly capped to reduce air exposure, to avoid storage at high temperatures, to run an engine for ten minutes to circulate the stabilizer through all components prior to storage, and to run the engine at intervals to purge stale fuel from the carburetor.<ref name="Ullmann2" />

Gasoline stability requirements are set by the standard [[ASTM International|ASTM]] D4814. This standard describes the various characteristics and requirements of automotive fuels for use over a wide range of operating conditions in ground vehicles equipped with spark-ignition engines.

===Combustion energy content===
A gasoline-fueled internal combustion engine obtains energy from the [[combustion]] of gasoline's various hydrocarbons with [[oxygen]] from the ambient air, yielding [[carbon dioxide]] and [[water]] as exhaust. The combustion of [[octane]], a representative species, performs the chemical reaction:

: {{chem2|2 C8H18 + 25 O2 -> 16 CO2 + 18 H2O}}

By weight, combustion of gasoline releases about {{convert|46.7|MJ/kg|kWh/kg MJ/lb|lk=on}} or by volume {{convert|33.6|MJ/L|kWh/L MJ/U.S.gal BTU/U.S.gal|lk=in|sp=us}}, quoting the [[lower heating value]].<ref>{{cite web |title=Energy Information Administration |url=http://www.eia.gov/Energyexplained/?page=about_energy_units |url-status=live |archive-url=https://web.archive.org/web/20151215012732/http://www.eia.gov/Energyexplained/?page=about_energy_units |archive-date=15 December 2015 |website=www.eia.gov |df=dmy-all}}</ref> Gasoline blends differ, and therefore actual energy content varies according to the season and producer by up to 1.75 percent more or less than the average.<ref>{{cite web |title=Fuel Properties Comparison |url=http://www.afdc.energy.gov/fuels/fuel_comparison_chart.pdf |url-status=dead |archive-url=https://web.archive.org/web/20161031034323/http://www.afdc.energy.gov/fuels/fuel_comparison_chart.pdf |archive-date=31 October 2016 |access-date=31 October 2016 |website=Alternative Fuels Data Center |df=dmy-all}}</ref> On average, about {{Convert|74|l|USgal|sp=us}} of gasoline are available from a barrel of crude oil (about 46 percent by volume), varying with the quality of the crude and the grade of the gasoline. The remainder is products ranging from tar to [[naphtha]].<ref>{{cite web |title=Oil Industry Statistics from Gibson Consulting |url=http://www.gravmag.com/oil.html |url-status=live |archive-url=https://web.archive.org/web/20080912232920/http://www.gravmag.com/oil.html |archive-date=12 September 2008 |access-date=31 July 2008 |df=dmy-all}}</ref>

A high-octane-rated fuel, such as [[liquefied petroleum gas]] (LPG), has an overall lower power output at the typical 10:1 [[compression ratio]] of an engine design optimized for gasoline fuel. An engine [[Engine tuning|tuned]] for [[Autogas|LPG]] fuel via higher compression ratios (typically 12:1) improves the power output. This is because higher-octane fuels allow for a higher compression ratio without knocking, resulting in a higher cylinder temperature, which improves [[Heat engine|efficiency]]. Also, increased mechanical efficiency is created by a higher compression ratio through the concomitant higher expansion ratio on the power stroke, which is by far the greater effect. The higher expansion ratio extracts more work from the high-pressure gas created by the combustion process. An [[Atkinson cycle]] engine uses the timing of the valve events to produce the benefits of a high expansion ratio without the disadvantages, chiefly detonation, of a high compression ratio. A high expansion ratio is also one of the two key reasons for the efficiency of [[diesel engine]]s, along with the elimination of pumping losses due to throttling of the intake airflow.

The lower energy content of LPG by liquid volume in comparison to gasoline is due mainly to its lower density. This lower density is a property of the lower [[molecular weight]] of [[propane]] (LPG's chief component) compared to gasoline's blend of various hydrocarbon compounds with heavier molecular weights than propane. Conversely, LPG's energy content by weight is higher than gasoline's due to a higher [[hydrogen]]-to-[[carbon]] ratio.

Molecular weights of the species in the representative octane combustion are 114, 32, 44, and 18 for C<sub>8</sub>H<sub>18</sub>, O<sub>2</sub>, CO<sub>2</sub>, and H<sub>2</sub>O, respectively; therefore {{Convert|1|kg|lb|spell=in}} of fuel reacts with {{Convert|3.51|kg|lb}} of oxygen to produce {{Convert|3.09|kg|lb}} of carbon dioxide and {{Convert|1.42|kg|lb}} of water.

==Octane rating==
{{main|Octane rating}}

[[Spark-ignition engine]]s are designed to burn gasoline in a controlled process called [[deflagration]]. However, the unburned mixture may autoignite by pressure and heat alone, rather than igniting from the [[spark plug]] at exactly the right time, causing a rapid pressure rise that can damage the engine. This is often referred to as [[engine knocking]] or end-gas knock. Knocking can be reduced by increasing the gasoline's resistance to [[Autoignition temperature|autoignition]], which is expressed by its octane rating. A detailed analysis further explores the conditions where premium fuel provides actual performance benefits versus when it is unnecessary.<ref>{{cite web |last=Gomez |first=Aly |title=Premium vs. Regular Gas: Are You Getting What You Pay For? |url=https://open.substack.com/pub/alygomez/p/premium-vs-regular-gas-are-you-getting |website=Substack |date=February 6, 2025 |access-date=February 8, 2025}}</ref>

Octane rating is measured relative to a mixture of [[2,2,4-Trimethylpentane|2,2,4-trimethylpentane]] (an [[isomer]] of [[octane]]) and n-[[heptane]]. There are different conventions for expressing octane ratings, so the same physical fuel may have several different octane ratings based on the measure used. One of the best known is the research octane number (RON).

The octane rating of typical commercially available gasoline varies by country. In [[Finland]], [[Sweden]], and [[Norway]], 95 RON is the standard for regular unleaded gasoline and 98 RON is also available as a more expensive option.

In the United Kingdom, over 95 percent of gasoline sold has 95 RON and is marketed as Unleaded or Premium Unleaded. Super Unleaded, with 97/98 RON and branded high-performance fuels (e.g., Shell V-Power, BP Ultimate) with 99 RON make up the balance. Gasoline with 102 RON may rarely be available for racing purposes.<ref>{{Cite web |title=Quality of petrol and diesel fuel used for road transport in the European Union (Reporting year 2013) |url=https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:52015DC0070&rid=1 |url-status=live |archive-url=https://web.archive.org/web/20210422161209/https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:52015DC0070&rid=1 |archive-date=22 April 2021 |access-date=July 31, 2020 |publisher=European Commission}}</ref><ref>{{Cite web |title=Types Of Car Fuel |url=https://www.simplemotoring.co.uk/car-fuel-types/ |url-status=live |archive-url=https://web.archive.org/web/20200925104546/https://www.simplemotoring.co.uk/car-fuel-types/ |archive-date=25 September 2020 |access-date=July 31, 2020}}</ref><ref>{{Cite web |title=Sunoco CFR Racing Fuel |url=https://aaoil.co.uk/product/sunoco-cfr-102-ron-90mon-2-2-oxygen/ |url-status=live |archive-url=https://web.archive.org/web/20201021192041/https://aaoil.co.uk/product/sunoco-cfr-102-ron-90mon-2-2-oxygen/ |archive-date=21 October 2020 |access-date=July 31, 2020}}</ref>

In the U.S., octane ratings in unleaded fuels vary between 85<ref>{{cite web |author=Ryan Lengerich Journal staff |title=85-octane warning labels not posted at many gasoline stations |url=http://rapidcityjournal.com/news/local/octane-warning-labels-not-posted-at-many-gas-stations/article_681e07bc-3cd3-5e0c-a3c7-c06fcc4d319c.html |url-status=live |archive-url=https://web.archive.org/web/20150615025518/http://rapidcityjournal.com/news/local/octane-warning-labels-not-posted-at-many-gas-stations/article_681e07bc-3cd3-5e0c-a3c7-c06fcc4d319c.html |archive-date=15 June 2015 |work=Rapid City Journal |date=17 July 2012 |df=dmy-all}}</ref> and 87 AKI (91–92 RON) for regular, 89–90 AKI (94–95 RON) for mid-grade (equivalent to European regular), up to 90–94 AKI (95–99 RON) for premium (European premium).
{| class="wikitable" style="text-align:center;"
|
|91
|92
|93
|94
|95
|96
|97
|98
|99
|100
|101
|102
|-
|Scandinavian
| colspan="4" scope="row" |
|Regular
|
|
|Premium
|
|-
|UK
| colspan="4" scope="row" |
|Regular
|
| colspan="2" scope="row" |Premium
|Super
|
|
|High-performance
|-
|USA
| colspan="2" scope="row" |Regular
|
| colspan="2" scope="row" |Mid-grade
| colspan="4" scope="row" |Premium
|}
As South Africa's largest city, [[Johannesburg]], is located on the [[Highveld]] at {{convert|1753|m|ft|sp=us}} above sea level, the [[Automobile Association of South Africa]] recommends 95-octane gasoline at low altitude and 93-octane for use in Johannesburg because "The higher the altitude the lower the air pressure, and the lower the need for a high octane fuel as there is no real performance gain".<ref>{{cite web |title=95/93 – What is the Difference, Really? |url=http://www.aa.co.za/about/press-room/press-releases/9593-what-is-the-difference-reallyij.html |url-status=dead |archive-url=https://web.archive.org/web/20161229112643/https://www.aa.co.za/about/press-room/press-releases/9593-what-is-the-difference-reallyij.html |archive-date=29 December 2016 |access-date=26 January 2017 |publisher=Automobile Association of South Africa (AA) |df=dmy-all }}</ref>

Octane rating became important as the military sought higher output for [[aircraft engine]]s in the late 1920s and the 1940s. A higher octane rating allows a higher [[compression ratio]] or [[supercharger]] boost, and thus higher temperatures and pressures, which translate to higher power output. Some scientists{{who|date=August 2018}} even predicted that a nation with a good supply of high-octane gasoline would have the advantage in air power. In 1943, the [[Rolls-Royce Merlin]] aero engine produced {{Convert|1320|hp|kW|order=flip}} using 100 RON fuel from a modest {{Convert|27|l|cuin|sp=us}} displacement. By the time of [[Operation Overlord]], both the RAF and USAAF were conducting some operations in Europe using 150 RON fuel (100/150 [[avgas]]), obtained by adding 2.5 percent [[aniline]] to 100-octane avgas.<ref name="Magazines19362">{{cite journal |author=Hearst Magazines |date=April 1936 |title=Popular Mechanics |url=https://books.google.com/books?id=lNsDAAAAMBAJ&pg=PA524 |url-status=live |journal=Popular Mechanics |publisher=Hearst Magazines |pages=524– |issn=0032-4558 |archive-url=https://web.archive.org/web/20130619054026/http://books.google.com/books?id=lNsDAAAAMBAJ&pg=PA524 |archive-date=19 June 2013 |df=dmy-all}}</ref> By this time, the Rolls-Royce Merlin 66 was developing {{Convert|2000|hp|kW|order=flip}} using this fuel.

==Additives==
{{See also|List of gasoline additives}}

===Antiknock additives===

====Tetraethyl lead====
{{main|Tetraethyl lead}}
<!--This section is linked from [[Lead]]-->

Gasoline, when used in high-[[Compression (physical)|compression]] internal combustion engines, tends to auto-ignite or "detonate" causing damaging [[engine knocking]] (also called "pinging" or "pinking"). To address this problem, [[Tetraethyllead|tetraethyl lead]] (TEL) was widely adopted as an additive for gasoline in the 1920s. With a growing awareness of the seriousness of the extent of environmental and health damage caused by lead compounds, however, and the incompatibility of lead with [[catalytic converter]]s, governments began to mandate reductions in gasoline lead.

In the U.S., the [[United States Environmental Protection Agency|Environmental Protection Agency]] issued regulations to reduce the lead content of leaded gasoline over a series of annual phases, scheduled to begin in 1973 but delayed by court appeals until 1976. By 1995, leaded fuel accounted for only 0.6 percent of total gasoline sales and under {{convert|2000|ST|t|abbr=off|sp=us|disp=output only}} ({{convert|{{convert|2000|ST|t|disp=output number only}}|t|ST LT|sp=us|disp=output only}}) of lead per year. From 1 January 1996, the [[Clean Air Act (United States)|U.S. Clean Air Act]] banned the sale of leaded fuel for use in on-road vehicles in the U.S. The use of TEL also necessitated other additives, such as [[dibromoethane]].

European countries began replacing lead-containing additives by the end of the 1980s and, by the end of the 1990s, leaded gasoline was banned within the entire European Union with an exception for [[Avgas#100LL (blue)|Avgas 100LL]] for [[general aviation]].<ref name="q566">{{cite web | last=Calderwood | first=Dave | title=Europe moves to ban lead in avgas | website=FLYER | date=8 March 2022 | url=https://flyer.co.uk/europe-moves-to-ban-lead-in-avgas/ | access-date=28 July 2024}}</ref> The UAE started to switch to unleaded in the early 2000s.<ref>{{Cite web |title=UAE switches to unleaded fuel |date=January 2003 |url=https://gulfnews.com/uae/uae-switches-to-unleaded-fuel-1.343442 |url-status=live |archive-url=https://web.archive.org/web/20200412131951/https://gulfnews.com/uae/uae-switches-to-unleaded-fuel-1.343442 |archive-date=12 April 2020 |access-date=12 April 2020}}</ref>

Reduction in the average lead content of human blood may be a major cause for falling violent crime rates around the world<ref name="WashingtonPostCrime2">{{cite news |last=Matthews |first= Dylan |date=22 April 2013 |title=Lead abatement, alcohol taxes and 10 other ways to reduce the crime rate without annoying the NRA |newspaper=Washington Post |url=https://www.washingtonpost.com/blogs/wonkblog/wp/2013/04/22/lead-abatement-alcohol-taxes-and-10-other-ways-to-reduce-the-crime-rate-without-annoying-the-nra/ |url-status=live |access-date=23 May 2013 |archive-url=https://web.archive.org/web/20130512052321/http://www.washingtonpost.com/blogs/wonkblog/wp/2013/04/22/lead-abatement-alcohol-taxes-and-10-other-ways-to-reduce-the-crime-rate-without-annoying-the-nra/ |archive-date=12 May 2013 |df=dmy-all}}</ref> including South Africa.<ref name="BusinessDayCrime2">{{cite web |last=Marrs |first= Dave |date=22 January 2013 |title=Ban on lead may yet give us respite from crime |url=http://www.bdlive.co.za/opinion/columnists/2013/01/22/ban-on-lead-may-yet-give-us-respite-from-crime |url-status=dead |archive-url=https://web.archive.org/web/20130406072130/http://www.bdlive.co.za/opinion/columnists/2013/01/22/ban-on-lead-may-yet-give-us-respite-from-crime |archive-date=6 April 2013 |access-date=23 May 2013 |publisher=Business Day |df=dmy-all}}</ref> A study found a correlation between leaded gasoline usage and violent crime (see [[Lead–crime hypothesis]]).<ref name="Reyes2">{{Cite web |last=Reyes |first=J. W. |date=2007 |url=https://www.nber.org/system/files/working_papers/w13097/w13097.pdf |title=The Impact of Childhood Lead Exposure on Crime |work=National Bureau of Economic Research. "a" ref citing Pirkle, Brody, et al. (1994) |access-date=26 May 2024 |archive-date=17 January 2024 |archive-url=https://web.archive.org/web/20240117041241/https://www.nber.org/system/files/working_papers/w13097/w13097.pdf |url-status=live }}</ref><ref>{{cite news |date=28 October 2007 |title=Ban on leaded petrol 'has cut crime rates around the world' |url=https://www.independent.co.uk/environment/green-living/ban-on-leaded-petrol-has-cut-crime-rates-around-the-world-398151.html |url-status=live |archive-url=https://web.archive.org/web/20170829032830/https://www.independent.co.uk/environment/green-living/ban-on-leaded-petrol-has-cut-crime-rates-around-the-world-398151.html |archive-date=29 August 2017 |df=dmy-all}}</ref> Other studies found no correlation.

In August 2021, the [[United Nations Environment Programme|UN Environment Programme]] announced that leaded gasoline had been eradicated worldwide, with [[Algeria]] being the last country to deplete its reserves. [[Secretary-General of the United Nations|UN Secretary-General]] [[António Guterres]] called the eradication of leaded petrol an "international success story". He also added: "Ending the use of leaded petrol will prevent more than one million premature deaths each year from heart disease, strokes and cancer, and it will protect children whose IQs are damaged by exposure to lead". [[Greenpeace]] called the announcement "the end of one toxic era".<ref>{{cite web |date=31 August 2021 |title=Highly polluting leaded petrol now eradicated from the world, says UN |url=https://www.bbc.com/news/world-58388810 |url-status=live |archive-url=https://web.archive.org/web/20220125025414/https://www.bbc.com/news/world-58388810 |archive-date=25 January 2022 |access-date=16 September 2021 |work=BBC News}}</ref> However, leaded gasoline continues to be used in aeronautic, auto racing, and off-road applications.<ref>{{cite web |last1=Miranda |first1=Leticia |last2=Farivar |first2=Cyrus |date=12 April 2021 |title=Leaded gas was phased out 25 years ago. Why are these planes still using toxic fuel? |url=https://www.nbcnews.com/business/business-news/leaded-gas-was-phased-out-25-years-ago-why-are-n1264970 |url-status=live |archive-url=https://web.archive.org/web/20210915233641/https://www.nbcnews.com/business/business-news/leaded-gas-was-phased-out-25-years-ago-why-are-n1264970 |archive-date=15 September 2021 |access-date=16 September 2021 |work=NBC News}}</ref> The use of leaded additives is still permitted worldwide for the formulation of some grades of [[aviation gasoline]] such as [[100LL]], because the required octane rating is difficult to reach without the use of leaded additives.

Different additives have replaced lead compounds. The most popular additives include [[aromatic hydrocarbon]]s, [[ether]]s ([[MTBE]] and [[ETBE]]), and [[alcohols]], most commonly [[ethanol]].

====<span class="anchor" id="Lead Replacement Petrol"></span> Lead replacement petrol====
Lead replacement petrol (LRP) was developed for vehicles designed to run on leaded fuels and incompatible with unleaded fuels. Rather than tetraethyllead, it contains other metals such as [[potassium]] compounds or [[methylcyclopentadienyl manganese tricarbonyl]] (MMT); these are purported to buffer soft exhaust valves and seats so that they do not suffer recession due to the use of unleaded fuel.

LRP was marketed during and after the phaseout of leaded motor fuels in the United Kingdom, [[Australia]], [[South Africa]], and some other countries.{{vague|date=August 2016}} Consumer confusion led to a widespread mistaken preference for LRP rather than unleaded,<ref>{{cite news |last=Seggie |first=Eleanor |date=5 August 2011 |title=More than 20% of SA cars still using lead-replacement petrol but only 1% need it |work=[[Engineering News (Creamer Media)|Engineering News]] |location=South Africa |url=http://www.engineeringnews.co.za/article/cleaner-fuels-for-sa-2011-08-05 |url-status=dead |access-date=30 March 2017 |archive-url=https://web.archive.org/web/20161013195145/http://www.engineeringnews.co.za/article/cleaner-fuels-for-sa-2011-08-05 |archive-date=13 October 2016 |df=dmy-all}}</ref> and LRP was phased out 8 to 10 years after the introduction of unleaded.<ref>{{cite news |last1=Clark |first1=Andrew |date=14 August 2002 |title=Petrol for older cars about to disappear |work=[[The Guardian]] |location=London |url=https://www.theguardian.com/uk/2002/aug/15/oil.business |url-status=live |access-date=30 March 2017 |archive-url=https://web.archive.org/web/20161229112618/https://www.theguardian.com/uk/2002/aug/15/oil.business |archive-date=29 December 2016 |df=dmy-all}}</ref>

Leaded gasoline was withdrawn from sale in Britain after 31 December 1999, seven years after [[European Economic Community|EEC]] regulations signaled the end of production for cars using leaded gasoline in member states. At this stage, a large percentage of cars from the 1980s and early 1990s which ran on leaded gasoline were still in use, along with cars that could run on unleaded fuel. However, the declining number of such cars on British roads saw many gasoline stations withdrawing LRP from sale by 2003.<ref>{{Cite news |date=15 August 2002 |title=AA warns over lead replacement fuel |work=[[The Daily Telegraph]] |location=London |url=https://www.telegraph.co.uk/motoring/news/2717637/AA-warns-over-lead-replacement-fuel.html |url-status=live |access-date=30 March 2017 |archive-url=https://web.archive.org/web/20170421115246/http://www.telegraph.co.uk/motoring/news/2717637/AA-warns-over-lead-replacement-fuel.html |archive-date=21 April 2017 |df=dmy-all}}</ref>

====MMT====
[[Methylcyclopentadienyl manganese tricarbonyl]] (MMT) is used in Canada and the U.S. to boost octane rating.<ref>{{cite web |last1=Hollrah |first1=Don P. |last2=Burns |first2=Allen M. |date=11 March 1991 |title=MMT Increases Octane While Reducing Emissions |url=http://www.ogj.com/articles/print/volume-89/issue-10/in-this-issue/refining/mmt-increases-octane-while-reducing-emissions.html |url-status=live |archive-url=https://web.archive.org/web/20161117072536/http://www.ogj.com/articles/print/volume-89/issue-10/in-this-issue/refining/mmt-increases-octane-while-reducing-emissions.html |archive-date=17 November 2016 |website=www.ogj.com |df=dmy-all}}</ref> Its use in the U.S. has been restricted by regulations, although it is currently allowed.<ref>{{cite web |date=5 October 2015 |title=EPA Comments on the Gasoline Additive MMT |url=https://www.epa.gov/gasoline-standards/epa-comments-gasoline-additive-mmt |url-status=live |archive-url=https://web.archive.org/web/20161117070650/https://www.epa.gov/gasoline-standards/epa-comments-gasoline-additive-mmt |archive-date=17 November 2016 |website=www.epa.gov |language=en |df=dmy-all}}</ref> Its use in the European Union is restricted by Article 8a of the Fuel Quality Directive<ref>{{cite web |title=Directive 2009/30/EC of the European Parliament and of the Council of 23 April 2009 |url=http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2009:140:0088:0113:EN:PDF |url-status=live |archive-url=https://web.archive.org/web/20160922172330/http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2009:140:0088:0113:EN:PDF |archive-date=22 September 2016 |access-date=July 31, 2020}}</ref> following its testing under the Protocol for the evaluation of effects of metallic fuel-additives on the emissions performance of vehicles.<ref>{{cite web |title=Protocol for the Evaluation of Effects of Metallic Fuel-Additives on the Emissions Performance of Vehicles |url=https://ec.europa.eu/clima/sites/clima/files/transport/fuel/docs/fuel_metallic_additive_protocol_en.pdf |url-status=live |archive-url=https://web.archive.org/web/20210301173052/https://ec.europa.eu/clima/sites/clima/files/transport/fuel/docs/fuel_metallic_additive_protocol_en.pdf |archive-date=1 March 2021 |access-date=July 31, 2020}}</ref>

===Fuel stabilizers (antioxidants and metal deactivators)===
[[File:Antioxidant.png|thumb|Substituted [[phenol]]s and derivatives of [[phenylenediamine]] are common antioxidants used to inhibit gum formation in gasoline]]
Gummy, sticky resin deposits result from [[Oxidation|oxidative]] degradation of gasoline during long-term storage. These harmful deposits arise from the oxidation of [[alkene]]s and other minor components in gasoline{{citation needed|date=March 2024}} (see [[drying oil]]s). Improvements in refinery techniques have generally reduced the susceptibility of gasolines to these problems. Previously, catalytically or thermally cracked gasolines were most susceptible to oxidation. The formation of gums is accelerated by copper salts, which can be neutralized by additives called [[metal deactivator]]s.

This degradation can be prevented through the addition of 5–100 ppm of [[antioxidant]]s, such as [[phenylenediamine]]s and other [[amine]]s.<ref name="Ullmann2" /> Hydrocarbons with a [[bromine number]] of 10 or above can be protected with the combination of unhindered or partially hindered [[phenol]]s and oil-soluble strong amine bases, such as hindered phenols. "Stale" gasoline can be detected by a [[colorimetric]] [[enzymatic]] test for [[organic peroxide]]s produced by oxidation of the gasoline.<ref>{{patent|AU|2000/72399 A1|Gasoline test kit}}</ref><!---See http://www.patentlens.net/patentlens/structured.cgi?patnum=AU_2000/72399_A1#show if template link fails--->

Gasolines are also treated with [[metal deactivator]]s, which are compounds that sequester (deactivate) metal salts that otherwise accelerate the formation of gummy residues. The metal impurities might arise from the engine itself or as contaminants in the fuel.

===Detergents===
Gasoline, as delivered at the pump, also contains additives to reduce internal engine carbon buildups, improve [[combustion]] and allow easier starting in cold climates. High levels of detergent can be found in [[Top Tier Detergent Gasoline]]s. The specification for Top Tier Detergent Gasolines was developed by four automakers: [[General Motors|GM]], [[Honda]], [[Toyota]], and [[BMW]]. According to the bulletin, the minimal U.S. [[United States Environmental Protection Agency|EPA]] requirement is not sufficient to keep engines clean.<ref>"Top Tier Detergent Gasoline (Deposits, Fuel Economy, No Start, Power, Performance, Stall Concerns)", GM Bulletin, 04-06-04-047, 06-Engine/Propulsion System, June 2004</ref> Typical detergents include [[Amine#Classification of amines|alkylamines]] and [[alkyl phosphate]]s at a level of 50–100 ppm.<ref name="Ullmann2" />

===Ethanol===
[[File:Corn vs Ethanol production.webp|thumb|300px|Corn vs Ethanol production in the United States
{{legend|#FFD932|Total corn production ([[bushel]]s) (left)}}
{{legend|B51700|Corn used for Ethanol fuel (bushels) (left)}}
{{legend-line|#313131 solid 3px|Percent of corn used for Ethanol (right)}}
]]
{{see also|Ethanol fuel|Common ethanol fuel mixtures}}

====European Union====
{{Unreferenced section|date=September 2024}}
In the EU, 5 percent [[ethanol]] can be added within the common gasoline spec (EN 228). Discussions are ongoing to allow 10 percent blending of ethanol (available in Finnish, French and German gasoline stations). In Finland, most gasoline stations sell 95E10, which is 10 percent ethanol, and 98E5, which is 5 percent ethanol. Most gasoline sold in Sweden has 5–15 percent ethanol added. Three different ethanol blends are sold in the Netherlands—E5, E10 and hE15. The last of these differs from standard ethanol–gasoline blends in that it consists of 15 percent [[hydrous ethanol]] (i.e., the ethanol–water [[azeotrope]]) instead of the anhydrous ethanol traditionally used for blending with gasoline.

From 2009 to 2022, renewable percentage in gasoline slowly increased from 5% to 10%, even though EU-produced ethanol can achieve a climate-neutral production capability and most EU cars can use E10. E10 availability is low even in larger countries like Germany (26%) and France (58%). 8 countries in the EU have not adopted E10 as of 2024.<ref>{{Cite web |title=Ethanol in gasoline: an immediate solution for renewables in road transport, the potential of E10 deployment in the EU – Summary of webinar by ETIP Bioenergy Working Group 3 – ETIP Bioenergy |url=https://www.etipbioenergy.eu/news/ethanol-in-gasoline-an-immediate-solution-for-renewables-in-road-transport-the-potential-of-e10-deployment-in-the-eu-summary-of-webinar-by-etip-bioenergy-working-group-3/ |access-date=2025-04-09 |language=en-US}}</ref>

====Brazil====
The [[Brazilian National Agency of Petroleum, Natural Gas and Biofuels]] (ANP) requires gasoline for automobile use to have 27.5 percent of ethanol added to its composition.<ref>{{cite web |title=MEDIDA PROVISÓRIA nº 532, de 2011 |url=http://www.senado.gov.br/atividade/materia/detalhes.asp?p_cod_mate=100053 |url-status=live |archive-url=https://web.archive.org/web/20110919030421/http://www.senado.gov.br/atividade/materia/detalhes.asp?p_cod_mate=100053 |archive-date=19 September 2011 |work=senado.gov.br |df=dmy-all}}</ref> Pure hydrated ethanol is also available as a fuel.

====Australia====
{{See also|Biofuel in Australia}}
Australia uses both [[Common ethanol fuel mixtures|E10]] (up to 10% ethanol) and E85 (up to 85% ethanol) in its gasoline. [[New South Wales]] mandated biofuel in its Biofuels Act 2007, and [[Queensland]] had a biofuel mandate since 2017. Fuel pumps must be clearly labeled with its ethanol/biodiesel content.<ref>{{Cite web |last=Commission |first=Australian Competition and Consumer |date=2023-02-20 |title=Ethanol and other biofuels |url=https://www.accc.gov.au/consumers/petrol-and-fuel/ethanol-and-other-biofuels |access-date=2025-05-19 |website=www.accc.gov.au |language=en}}</ref>

==== U.S. ====
{{Unreferenced section|date=September 2024}}
The federal [[Renewable Fuel Standard]] (RFS) effectively requires refiners and blenders to blend renewable [[biofuel]]s (mostly ethanol) with gasoline, sufficient to meet a growing annual target of total gallons blended. Although the mandate does not require a specific percentage of ethanol, annual increases in the target combined with declining [[gasoline consumption]] have caused the typical ethanol content in gasoline to approach 10 percent. Most fuel pumps display a sticker that states that the fuel may contain up to 10 percent ethanol, an intentional disparity that reflects the varying actual percentage. In parts of the U.S., ethanol is sometimes added to gasoline without an indication that it is a component.

====India====
In October 2007, the [[Government of India]] decided to make five percent ethanol blending (with gasoline) mandatory. Currently, 10 percent ethanol blended product (E10) is being sold in various parts of the country.<ref name="Government to take a call on ethanol price soon2">{{cite news |date=21 November 2011 |title=Government to take a call on ethanol price soon |work=The Hindu |location=Chennai, India |url=http://www.thehindu.com/news/national/article2647940.ece |url-status=live |access-date=25 May 2012 |archive-url=https://web.archive.org/web/20120505123807/http://www.thehindu.com/news/national/article2647940.ece |archive-date=5 May 2012 |df=dmy-all}}</ref><ref name="India to raise ethanol blending in gasoline to 10%2">{{cite news |date=22 November 2011 |title=India to raise ethanol blending in gasoline to 10% |url=http://www.commodityonline.com/news/india-to-raise-ethanol-blending-in-gasoline-to-10-43892-3-43893.html |url-status=dead |access-date=25 May 2012 |archive-url=https://web.archive.org/web/20140407231713/http://www.commodityonline.com/news/india-to-raise-ethanol-blending-in-gasoline-to-10-43892-3-43893.html |archive-date=7 April 2014 |df=dmy-all}}</ref> Ethanol has been found in at least one study to damage catalytic converters.<ref>{{cite web |title=European Biogas Association |url=http://european-biogas.eu/wp-content/uploads/2014/02/022013_Fuel-impact-on-the-aging-of-TWC%E2%80%99s-under-real-driving-conditions_Winkler-et-al.pdf |url-status=dead |archive-url=https://web.archive.org/web/20160324165803/http://european-biogas.eu/wp-content/uploads/2014/02/022013_Fuel-impact-on-the-aging-of-TWC%E2%80%99s-under-real-driving-conditions_Winkler-et-al.pdf |archive-date=24 March 2016 |access-date=2016-03-16 |df=dmy-all}}</ref>

===Dyes===
{{Main|Fuel dyes}}

Though gasoline is a naturally colorless liquid, many gasolines are dyed in various colors to indicate their composition and acceptable uses. In Australia, the lowest grade of gasoline (RON 91) was dyed a light shade of red/orange, but is now the same color as the medium grade (RON 95) and high octane (RON 98), which are dyed yellow.<ref>{{cite web |title=The Color of Australian Unleaded Petrol Is Changing To Red/Orange |url=http://www.aip.com.au/topics/mr_pdf/AIP_media_release_280912.pdf |url-status=dead |archive-url=https://web.archive.org/web/20130409211243/http://www.aip.com.au/topics/mr_pdf/AIP_media_release_280912.pdf |archive-date=9 April 2013 |access-date=2012-11-22 |df=dmy-all }}</ref> In the U.S., aviation gasoline ([[avgas]]) is dyed to identify its octane rating and to distinguish it from kerosene-based jet fuel, which is left colorless.<ref>{{cite web |date=17 May 2008 |title=EAA – Avgas Grades |url=http://www.eaa.org/autofuel/avgas/grades.asp |url-status=dead |archive-url=https://web.archive.org/web/20080517022056/http://www.eaa.org/autofuel/avgas/grades.asp |archive-date=17 May 2008 |access-date=6 October 2012 }}</ref> In Canada, the gasoline for marine and farm use is dyed red and is not subject to fuel excise tax in most provinces.<ref>{{cite web |title=Fuel Taxes & Road Expenditures: Making the Link |url=https://umanitoba.ca/faculties/management/ti/media/docs/Fuel_Taxes_Road_Expenditures_1999.pdf |url-status=live |archive-url=https://web.archive.org/web/20140410200621/http://umanitoba.ca/faculties/management/ti/media/docs/Fuel_Taxes_Road_Expenditures_1999.pdf |archive-date=10 April 2014 |access-date=26 September 2017 |page=2 |df=dmy-all}}</ref>

===Oxygenate blending===
[[Oxygenate]] blending adds [[oxygen]]-bearing compounds such as [[methanol]], [[Methyl tert-butyl ether|MTBE]], [[Ethyl tert-butyl ether|ETBE]], [[Tert-Amyl methyl ether|TAME]], [[Tert-Amyl ethyl ether|TAEE]], [[ethanol]], and [[biobutanol]]. The presence of these oxygenates reduces the amount of [[carbon monoxide]] and unburned fuel in the exhaust. In many areas throughout the U.S., oxygenate blending is mandated by EPA regulations to reduce smog and other airborne pollutants. For example, in Southern California fuel must contain two percent oxygen by weight, resulting in a mixture of 5.6 percent ethanol in gasoline. The resulting fuel is often known as reformulated gasoline (RFG) or oxygenated gasoline, or, in the case of California, California reformulated gasoline (CARBOB). The federal requirement that RFG contain oxygen was dropped on 6 May 2006 because the industry had developed [[Volatile organic compound|VOC]]-controlled RFG that did not need additional oxygen.<ref>{{cite web |date=22 February 2006 |title=Removal of Reformulated Gasoline Oxygen Content Requirement (national) and Revision of Commingling Prohibition to Address Non-0xygenated Reformulated Gasoline (national) |url=http://www.epa.gov/otaq/rfg_regs.htm#usage |url-status=live |archive-url=https://web.archive.org/web/20050920073346/http://www.epa.gov/otaq/rfg_regs.htm#usage |archive-date=20 September 2005 |publisher=[[U.S. Environmental Protection Agency]] |df=dmy-all}}</ref>

MTBE was phased out in the U.S. due to groundwater contamination and the resulting regulations and lawsuits. Ethanol and, to a lesser extent, ethanol-derived ETBE are common substitutes. A common ethanol-gasoline mix of 10 percent ethanol mixed with gasoline is called [[Ethanol fuel|gasohol]] or E10, and an ethanol-gasoline mix of 85 percent ethanol mixed with gasoline is called [[E85]]. The most extensive use of ethanol takes place in [[Brazil]], where the ethanol is derived from [[sugarcane]]. In 2004, over {{convert|3.4|e9U.S.gal|e9l|sp=us|order=flip}} of ethanol was produced in the U.S. for fuel use, mostly from [[Maize|corn]] and sold as E10. E85 is slowly becoming available in much of the U.S., though many of the relatively few stations vending E85 are not open to the general public.<ref>{{cite web |title=Alternative Fueling Station Locator |url=http://www.eere.energy.gov/afdc/fuels/stations_locator.html |url-status=dead |archive-url=https://web.archive.org/web/20080714060953/http://www.eere.energy.gov/afdc/fuels/stations_locator.html |archive-date=14 July 2008 |access-date=14 July 2008 |publisher=[[U.S. Department of Energy]] |df=dmy-all}}</ref>

The use of [[bioethanol]] and bio-methanol, either directly or indirectly by conversion of ethanol to bio-ETBE, or methanol to bio-MTBE is encouraged by the European Union [[Directive on the Promotion of the use of biofuels and other renewable fuels for transport]]. Since producing bioethanol from fermented sugars and starches involves [[distillation]], though, ordinary people in much of Europe cannot legally ferment and distill their own bioethanol at present (unlike in the U.S., where getting a [[BATF]] distillation permit has been easy since the [[1973 oil crisis]]).

==Safety==
[[File:DOT hazmat class 3 (alt 3).svg|thumb|HAZMAT class 3 gasoline]]

===Toxicity===
The [[safety data sheet]] for a 2003 [[Texas|Texan]] unleaded gasoline shows at least 15 hazardous chemicals occurring in various amounts, including [[benzene]] (up to five percent by volume), [[toluene]] (up to 35 percent by volume), [[naphthalene]] (up to one percent by volume), [[1,2,4-Trimethylbenzene|trimethylbenzene]] (up to seven percent by volume), [[Methyl tert-butyl ether|methyl ''tert''-butyl ether]] (MTBE) (up to 18 percent by volume, in some states), and about 10 others.<ref>{{Cite web |url=http://firstfuelbank.com/msds/Tesoro.pdf |title=Material safety data sheet |archive-url=https://web.archive.org/web/20070928104058/http://firstfuelbank.com/msds/Tesoro.pdf|archive-date=28 September 2007 |work=Tesoro petroleum Companies, Inc., U.S. |date=8 February 2003}}</ref> Hydrocarbons in gasoline generally exhibit low acute toxicities, with [[LD50]] of 700–2700&nbsp;mg/kg for simple aromatic compounds.<ref>Karl Griesbaum et al. "Hydrocarbons" in Ullmann's Encyclopedia of Industrial Chemistry 2005, Wiley-VCH, Weinheim. {{doi|10.1002/14356007.a13_227}}</ref> Benzene and many antiknocking additives are [[carcinogenic]].

People can be exposed to gasoline in the workplace by swallowing it, breathing in vapors, skin contact, and eye contact. Gasoline is toxic. The [[National Institute for Occupational Safety and Health]] (NIOSH) has also designated gasoline as a carcinogen.<ref>{{cite web |title=CDC – NIOSH Pocket Guide to Chemical Hazards – Gasoline |url=https://www.cdc.gov/niosh/npg/npgd0299.html |url-status=live |archive-url=https://web.archive.org/web/20151016080051/http://www.cdc.gov/niosh/npg/npgd0299.html |archive-date=16 October 2015 |access-date=3 November 2015 |website=www.cdc.gov |df=dmy-all}}</ref> Physical contact, ingestion, or inhalation can cause health problems. Since ingesting large amounts of gasoline can cause permanent damage to major organs, a call to a local poison control center or emergency room visit is indicated.<ref>{{Cite journal |author=E Reese and R D Kimbrough |date=December 1993 |title=Acute toxicity of gasoline and some additives |journal=Environmental Health Perspectives |volume=101 |issue=Suppl 6 |pages=115–131 |doi=10.1289/ehp.93101s6115 |pmc=1520023 |pmid=8020435}}</ref>

Contrary to [[common misconception]], swallowing gasoline does not generally require special emergency treatment, and inducing vomiting does not help, and can make it worse. According to poison specialist Brad Dahl, "even two mouthfuls wouldn't be that dangerous as long as it goes down to your stomach and stays there or keeps going". The U.S. [[Centers for Disease Control and Prevention|CDC]]'s [[Agency for Toxic Substances and Disease Registry]] says not to induce vomiting, [[lavage]], or administer [[Activated carbon|activated charcoal]].<ref>{{Citation |author=University of Utah Poison Control Center |title=Dos and Don'ts in Case of Gasoline Poisoning |date=24 June 2014 |url=https://healthcare.utah.edu/the-scope/shows.php?shows=0_g9tzppx4 |archive-url=https://web.archive.org/web/20201108090627/https://healthcare.utah.edu/the-scope/shows.php?shows=0_g9tzppx4 |publisher=[[University of Utah]] |access-date=15 October 2018 |archive-date=8 November 2020 |url-status=live}}</ref><ref>{{Citation |author=Agency for Toxic Substances and Disease Registry |title=Medical Management Guidelines for Gasoline (Mixture) CAS# 86290-81-5 and 8006-61-9 |date=21 October 2014 |url=https://www.atsdr.cdc.gov/MMG/MMG.asp?id=465&tid=83 |archive-url=https://web.archive.org/web/20201114004205/https://www.atsdr.cdc.gov/MMG/MMG.asp?id=465&tid=83 |publisher=[[Centers for Disease Control and Prevention]] |access-date=13 December 2018 |archive-date=14 November 2020 |author-link=Agency for Toxic Substances and Disease Registry |url-status=live}}</ref>

===Inhalation for intoxication===
[[Inhalant|Inhaled]] (huffed) gasoline vapor is a common intoxicant. Users concentrate and inhale gasoline vapor in a manner not intended by the manufacturer to produce [[euphoria]] and [[Substance intoxication|intoxication]]. Gasoline inhalation has become epidemic in some poorer communities and indigenous groups in Australia, Canada, New Zealand, and some Pacific Islands.<ref name="gasoline Sniffing Fact File2">{{Cite web |url=https://www.abc.net.au/health/library/stories/2005/11/24/1831506.htm |title=Petrol Sniffing Fact File |website=[[Australian Broadcasting Corporation]] |access-date=26 May 2024 |archive-date=26 May 2024 |archive-url=https://web.archive.org/web/20240526150145/https://www.abc.net.au/health/library/stories/2005/11/24/1831506.htm |url-status=live }}</ref> The practice is thought to cause severe organ damage, along with other effects such as [[intellectual disability]] and various [[cancer]]s.<ref>{{cite journal |title=Low IQ and Gasoline Huffing: The Perpetuation Cycle |year=2005 |doi=10.1176/appi.ajp.162.5.1020-a |url=https://www.researchgate.net/publication/7873998 |url-status=live |archive-url=https://web.archive.org/web/20170814215234/https://www.researchgate.net/publication/7873998_Low_IQ_and_Gasoline_Huffing_The_Perpetuation_Cycle |archive-date=14 August 2017 |df=dmy-all|last1=Yip |first1=Leona |last2=Mashhood |first2=Ahmed |last3=Naudé |first3=Suné |journal=American Journal of Psychiatry |volume=162 |issue=5 |pages=1020–1021 |pmid=15863813 }}</ref><ref>{{cite web |date=16 May 2013 |title=Rising Trend: Sniffing Gasoline – Huffing & Inhalants |url=https://www.addiction.com/3385/gas-sniffing-form-substance-abuse/ |url-status=dead |archive-url=https://web.archive.org/web/20161220203248/https://www.addiction.com/3385/gas-sniffing-form-substance-abuse/ |archive-date=20 December 2016 |access-date=12 December 2016 |df=dmy-all }}</ref><ref>{{cite web |title=Petrol Sniffing / Gasoline Sniffing |url=http://alcoholrehab.com/drug-addiction/petrol-sniffing-gasoline-sniffing/ |url-status=dead |archive-url=https://web.archive.org/web/20161221072052/http://alcoholrehab.com/drug-addiction/petrol-sniffing-gasoline-sniffing/ |archive-date=21 December 2016 |access-date=12 December 2016 |df=dmy-all}}</ref><ref>{{cite web |title=Benzene and Cancer Risk |url=https://www.cancer.org/cancer/cancer-causes/benzene.html |url-status=live |archive-url=https://web.archive.org/web/20210125204501/https://www.cancer.org/cancer/cancer-causes/benzene.html |archive-date=25 January 2021 |access-date=7 December 2020 |website=[[American Cancer Society]]}}</ref>

In Canada, Native children in the isolated Northern Labrador community of [[Davis Inlet, Newfoundland and Labrador|Davis Inlet]] were the focus of national concern in 1993, when many were found to be sniffing gasoline. The Canadian and provincial [[Newfoundland and Labrador]] governments intervened on several occasions, sending many children away for treatment. Despite being moved to the new community of [[Natuashish, Newfoundland and Labrador|Natuashish]] in 2002, serious inhalant abuse problems have continued. Similar problems were reported in [[Sheshatshiu, Newfoundland and Labrador|Sheshatshiu]] in 2000 and also in [[Pikangikum First Nation]].<ref>{{cite web |last=Lauwers |first=Bert |date=1 June 2011 |title=The Office of the Chief Coroner's Death Review of the Youth Suicides at the Pikangikum First Nation, 2006–2008 |url=http://www.mcscs.jus.gov.on.ca/english/DeathInvestigations/office_coroner/PublicationsandReports/Pikangikum/PIK_report.html |url-status=dead |archive-url=https://web.archive.org/web/20120930122313/http://www.mcscs.jus.gov.on.ca//english/DeathInvestigations/office_coroner/PublicationsandReports/Pikangikum/PIK_report.html |archive-date=30 September 2012 |access-date=2 October 2011 |publisher=Office of the Chief Coroner of Ontario }}</ref> In 2012, the issue once again made the news media in Canada.<ref>{{cite web |title=Labrador Innu kids sniffing gas again to fight boredom |url=https://www.cbc.ca/news/canada/newfoundland-labrador/labrador-innu-kids-sniffing-gas-again-to-fight-boredom-1.1272679 |url-status=live |archive-url=https://web.archive.org/web/20120618224149/http://www.cbc.ca/news/canada/newfoundland-labrador/story/2012/06/18/nl-natuashish-sniffing-618.html |archive-date=18 June 2012 |access-date=18 June 2012 |publisher=[[CBC.ca]] |df=dmy-all}}</ref>

{{see also|Indigenous Australian#Substance abuse}}

Australia has long faced a petrol (gasoline) sniffing problem in isolated and impoverished [[Australian Aborigines|aboriginal]] communities. Although some sources argue that sniffing was introduced by U.S. [[Soldier|servicemen]] stationed in the nation's [[Top End]] during [[World War II]]<ref>{{cite journal |last=Wortley |first=R.P. |date=29 August 2006 |title=Anangu Pitjantjatjara Yankunytjatjara Land Rights (Regulated Substances) Amendment Bill |url=http://www.parliament.sa.gov.au/SAN/Attachments/Hansard/2006/LC/WH290806.LC.htm |journal=Legislative Council (South Australia) |publisher=Hansard |archive-url=https://web.archive.org/web/20070929121901/http://www.parliament.sa.gov.au/SAN/Attachments/Hansard/2006/LC/WH290806.LC.htm |archive-date=29 September 2007 |access-date=27 December 2006 |url-status=dead }}</ref> or through experimentation by 1940s-era [[Cobourg Peninsula]] sawmill workers,<ref>{{cite journal |last=Brady |first=Maggie |date=27 April 2006 |title=Community Affairs Reference Committee Reference: Petrol sniffing in remote Aboriginal communities |url=http://www.aph.gov.au/hansard/senate/commttee/S9271.pdf |url-status=dead |journal=Official Committee Hansard (Senate) |publisher=Hansard |page=11 |archive-url=https://web.archive.org/web/20060912011023/http://www.aph.gov.au/hansard/senate/commttee/S9271.pdf |archive-date=12 September 2006 |access-date=20 March 2006 }}</ref> other sources claim that inhalant abuse (such as glue inhalation) emerged in Australia in the late 1960s.<ref>{{cite report |url=http://archives.drugabuse.gov/pdf/monographs/148.pdf |title=Epidemiology of Inhalant Abuse: An International Perspective |publisher=National Institute on Drug Abuse |id=NIDA Research Monograph 148 |archive-url=https://web.archive.org/web/20161005024204/http://archives.drugabuse.gov/pdf/monographs/148.pdf |archive-date=5 October 2016 |url-status=dead |year=1995 |editor-first=Nicholas |editor-last=Kozel |editor2-first=Zili |editor2-last=Sloboda |editor3=Mario De La Rosa |accessdate=2 August 2020 }}</ref> Chronic, heavy petrol sniffing appears to occur among remote, impoverished [[Indigenous Australians|indigenous]] communities, where the ready accessibility of petrol has helped to make it a common substance for abuse.

In Australia, petrol sniffing now occurs widely throughout remote Aboriginal communities in the [[Northern Territory]], [[Western Australia]], northern parts of [[South Australia]], and [[Queensland]].<ref>{{cite news |title=Petrol-sniffing reports in Central Australia increase as kids abuse low aromatic Opal fuel |newspaper=ABC News |date=10 May 2022 |url=https://www.abc.net.au/news/2022-05-11/petrol-sniffing-concerns-rise-in-central-australia-/101052088 |access-date=16 May 2022 |archive-date=16 May 2022 |archive-url=https://web.archive.org/web/20220516000246/https://www.abc.net.au/news/2022-05-11/petrol-sniffing-concerns-rise-in-central-australia-/101052088 |url-status=live }}</ref> The number of people sniffing petrol goes up and down over time as young people experiment or sniff occasionally. "Boss", or chronic, sniffers may move in and out of communities; they are often responsible for encouraging young people to take it up.<ref>{{cite web |last=Williams |first=Jonas |date=March 2004 |title=Responding to petrol sniffing on the Anangu Pitjantjatjara Lands: A case study |url=http://www.humanrights.gov.au/social_justice/sj_report/sjreport03/chap4.html |url-status=dead |archive-url=https://web.archive.org/web/20070831173214/http://humanrights.gov.au/social_justice/sj_report/sjreport03/chap4.html |archive-date=31 August 2007 |access-date=27 December 2006 |work=Social Justice Report 2003 |publisher=Human Rights and Equal Opportunity Commission |df=dmy-all}}</ref> In 2005, the [[Government of Australia]] and [[BP|BP Australia]] began the usage of [[Opal (fuel)|Opal fuel]] in remote areas prone to petrol sniffing.<ref>{{Cite web |url=http://www.aph.gov.au/senate/Committee/clac_ctte/petrol_sniffing/submissions/sub03.pdf |title=Submission to the Senate Community Affairs References Committee by BP Australia Pty Ltd |archive-url=https://web.archive.org/web/20070614103002/http://www.aph.gov.au/Senate/committee/clac_ctte/petrol_sniffing/submissions/sub03.pdf|archive-date=14 June 2007|work=Parliament of Australia Web Site|access-date=8 June 2007}}</ref> Opal is a non-sniffable fuel (which is much less likely to cause a high) and has made a difference in some indigenous communities.

===Flammability===
[[File:Gasoline-fire.png|thumb|Uncontrolled burning of gasoline produces large quantities of [[soot]] and [[carbon monoxide]].]]
Gasoline is flammable with low [[flash point]] of {{Convert|-23|C|F}}.  Gasoline has a [[lower explosive limit]] of 1.4 percent by volume and an [[upper explosive limit]] of 7.6 percent. If the concentration is below 1.4 percent, the air-gasoline mixture is too lean and does not ignite. If the concentration is above 7.6 percent, the mixture is too rich and also does not ignite. However, gasoline vapor rapidly mixes and spreads with air, making unconstrained gasoline quickly flammable.

===Gasoline exhaust===
The [[exhaust gas]] generated by burning gasoline is harmful to both the environment and to human health. After CO is inhaled into the human body, it readily combines with hemoglobin in the blood, and its affinity is 300 times that of oxygen. Therefore, the hemoglobin in the lungs combines with CO instead of oxygen, causing the human body to be [[Hypoxia (medical)|hypoxic]], causing headaches, dizziness, vomiting, and other poisoning symptoms. In severe cases, it may lead to death.<ref>{{Cite web |title=Carbon Monoxide Poisoning |url=https://www.osha.gov/sites/default/files/publications/carbonmonoxide-factsheet.pdf |url-status=live |archive-url=https://web.archive.org/web/20220101071121/http://www.osha.gov/sites/default/files/publications/carbonmonoxide-factsheet.pdf |archive-date=1 January 2022 |access-date=12 December 2021}}</ref><ref>{{Cite web |title=Carbon monoxide poisoning - Symptoms and causes |url=https://www.mayoclinic.org/diseases-conditions/carbon-monoxide/symptoms-causes/syc-20370642 |url-status=live |archive-url=https://web.archive.org/web/20211212225133/https://www.mayoclinic.org/diseases-conditions/carbon-monoxide/symptoms-causes/syc-20370642 |archive-date=12 December 2021 |access-date=2021-12-12 |website=Mayo Clinic |language=en}}</ref> Hydrocarbons only affect the human body when their concentration is quite high, and their toxicity level depends on the chemical composition. The hydrocarbons produced by incomplete combustion include alkanes, aromatics, and aldehydes. Among them, a concentration of methane and ethane over {{Convert|35|g/m3|oz/cuft|abbr=on}} will cause loss of consciousness or suffocation, a concentration of pentane and hexane over {{Convert|45|g/m3|oz/cuft|abbr=on}} will have an anesthetic effect, and aromatic hydrocarbons will have more serious effects on health, blood toxicity, [[neurotoxicity]], and cancer. If the concentration of benzene exceeds 40 ppm, it can cause leukemia, and xylene can cause headache, dizziness, nausea, and vomiting. Human exposure to large amounts of aldehydes can cause eye irritation, nausea, and dizziness. In addition to carcinogenic effects, long-term exposure can cause damage to the skin, liver, kidneys, and cataracts.<ref name="x-engineer.org">{{Cite web |last=x-engineer.org |title=Effects of vehicle pollution on human health – x-engineer.org |url=https://x-engineer.org/effects-vehicle-pollution-human-health/ |url-status=live |archive-url=https://web.archive.org/web/20211212225153/https://x-engineer.org/effects-vehicle-pollution-human-health/ |archive-date=12 December 2021 |access-date=2021-12-12 |language=en-US}}</ref> After NO<sub>x</sub> enters the alveoli, it has a severe stimulating effect on the lung tissue. It can irritate the conjunctiva of the eyes, cause tearing, and cause pink eyes. It also has a stimulating effect on the nose, pharynx, throat, and other organs. It can cause acute wheezing, breathing difficulties, red eyes, sore throat, and dizziness causing poisoning.<ref name="x-engineer.org" /><ref>{{Cite web |title=NOx gases in diesel car fumes: Why are they so dangerous? |url=https://phys.org/news/2015-09-nox-gases-diesel-car-fumes.html |url-status=live |archive-url=https://web.archive.org/web/20211212225135/https://phys.org/news/2015-09-nox-gases-diesel-car-fumes.html |archive-date=12 December 2021 |access-date=2021-12-12 |website=phys.org |language=en}}</ref> [[Fine particulate matter|Fine particulates]] are also dangerous to health.<ref name="canada-2015">{{Cite web |last= |first= |date=2015-10-13 |title=Human Health Risk Assessment for Gasoline Exhaust |url=https://www.canada.ca/en/health-canada/services/publications/healthy-living/human-health-risk-assessment-gasoline-exhaust-summary.html |access-date=2024-09-26 |website=www.canada.ca}}</ref>

== Environmental effect ==
The [[air pollution]] in many large cities has changed from coal-burning pollution to "motor vehicle pollution". In the U.S., transportation is the largest source of carbon emissions, accounting for 30 percent of the total carbon footprint of the U.S.<ref>{{Cite web |title=Facts About Gasoline |url=https://www.coltura.org/gasfacts |url-status=live |archive-url=https://web.archive.org/web/20211209181408/https://www.coltura.org/gasfacts |archive-date=9 December 2021 |access-date=2021-12-12 |website=Coltura - moving beyond gasoline |language=en-US}}</ref> Combustion of gasoline produces {{convert|2.35|kg/L|lb/U.S.gal|sp=us}} of carbon dioxide, a [[greenhouse gas]].<ref>{{cite magazine |date=1 November 2006 |title=How Gasoline Becomes CO2 |url=http://www.slate.com/id/2152685/ |url-status=live |magazine=Slate Magazine |archive-url=https://web.archive.org/web/20110820030124/http://www.slate.com/id/2152685/ |archive-date=20 August 2011 |df=dmy-all}}</ref><ref name="US Energy Information Administration2">{{citation-attribution|1={{cite web |title=How much carbon dioxide is produced by burning gasoline and diesel fuel? |url=http://www.eia.gov/tools/faqs/faq.cfm?id=307&t=11 |url-status=live |archive-url=https://web.archive.org/web/20131027195801/http://www.eia.gov/tools/faqs/faq.cfm?id=307&t=11 |archive-date=27 October 2013 |publisher=U.S. Energy Information Administration (EIA) |df=dmy-all}} }}</ref>

Unburnt gasoline and [[Automobile emissions control#Evaporative emissions control|evaporation from the tank]], when in the [[atmosphere]], react in [[sunlight]] to produce [[photochemical smog]]. Vapor pressure initially rises with some addition of ethanol to gasoline, but the increase is greatest at 10 percent by volume.<ref>{{Cite journal |author1=V. F. Andersen |author2=J. E. Anderson |author3=T. J. Wallington |author4=S. A. Mueller |author5=O. J. Nielsen |date=May 21, 2010 |title=Vapor Pressures of Alcohol−Gasoline Blends |journal=Energy Fuels |volume=24 |issue=6 |pages=3647–3654 |doi=10.1021/ef100254w}}</ref> At higher concentrations of ethanol above 10 percent, the vapor pressure of the blend starts to decrease. At a 10 percent ethanol by volume, the rise in vapor pressure may potentially increase the problem of photochemical smog. This rise in vapor pressure could be mitigated by increasing or decreasing the percentage of ethanol in the gasoline mixture. The chief risks of such leaks come not from vehicles, but gasoline delivery truck accidents and leaks from storage tanks. Because of this risk, most (underground) storage tanks now have extensive measures in place to detect and prevent any such leaks, such as monitoring systems (Veeder-Root, Franklin Fueling).

Production of gasoline consumes {{convert|0.63|U.S.gal/mi|L/km|sp=us|order=flip}} of [[water]] by driven distance.<ref>{{cite web |title=Water Intensity of Transportation |url=http://www.circleofblue.org/waternews/wp-content/uploads/2010/08/Webber-water-in-transportation.pdf |url-status=dead |archive-url=https://web.archive.org/web/20130915174902/http://www.circleofblue.org/waternews/wp-content/uploads/2010/08/Webber-water-in-transportation.pdf |archive-date=15 September 2013 |access-date=6 October 2016 }}</ref>

Gasoline use causes a variety of deleterious effects to the human population and to the climate generally. The harms imposed include a higher rate of premature death and ailments, such as [[asthma]], caused by [[air pollution]], higher healthcare costs for the public generally, decreased [[crop yields]], missed work and school days due to illness, increased [[flood]]ing and other [[extreme weather]] events linked to [[global climate change]], and other social costs. The costs imposed on society and the planet are estimated to be $3.80 per gallon of gasoline, in addition to the price paid at the pump by the user. The damage to the health and climate caused by a gasoline-powered vehicle greatly exceeds that caused by electric vehicles.<ref>{{Cite web |last=University |first=Duke |title=New models yield clearer picture of emissions' true costs |url=https://phys.org/news/2015-03-yield-clearer-picture-emissions-true.html |access-date=2024-05-26 |website=phys.org |language=en |archive-date=25 November 2020 |archive-url=https://web.archive.org/web/20201125024316/https://phys.org/news/2015-03-yield-clearer-picture-emissions-true.html |url-status=live }}</ref><ref>{{Cite journal |last1=Shindell |first1=Drew T. |year=2015 |title=The social cost of atmospheric release |journal=Climatic Change |volume=130 |issue=2 |pages=313–326 |bibcode=2015ClCh..130..313S |doi=10.1007/s10584-015-1343-0 |doi-access=free |s2cid=41970160|hdl=10419/85245 |hdl-access=free }}</ref>

Gasoline can be released into the environment as an uncombusted liquid fuel, as a flammable liquid, or as a vapor by way of leakages occurring during its production, handling, transport and delivery.<ref>{{Cite web |date=13 October 2014 |title=Preventing and Detecting Underground Storage Tank (UST) Releases |url=https://www.epa.gov/ust/preventing-and-detecting-underground-storage-tank-ust-releases |url-status=live |archive-url=https://web.archive.org/web/20201210005946/https://www.epa.gov/ust/preventing-and-detecting-underground-storage-tank-ust-releases |archive-date=10 December 2020 |access-date=14 November 2018 |publisher=United States Environmental Protection Agency |language=en}}</ref> Gasoline contains known [[carcinogen]]s,<ref>{{cite web |title=Evaluation of the Carcinogenicity of Unleaded Gasoline |url=http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=36176#Download |url-status=live |archive-url=https://web.archive.org/web/20100627032708/http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=36176#Download |archive-date=27 June 2010 |work=U.S. Environmental Protection Agency |df=dmy-all}}</ref><ref>{{cite journal |last1=Mehlman |first1=MA |date=1990 |title=Dangerous properties of petroleum-refining products: carcinogenicity of motor fuels (gasoline). |journal=Teratogenesis, Carcinogenesis, and Mutagenesis |volume=10 |issue=5 |pages=399–408 |doi=10.1002/tcm.1770100505 |pmid=1981951 | issn = 2472-1727 }}</ref><ref>{{cite journal |last1=Baumbach |first1=JI |last2=Sielemann |first2=S |last3=Xie |first3=Z |last4=Schmidt |first4=H |date=15 March 2003 |title=Detection of the gasoline components methyl tert-butyl ether, benzene, toluene, and m-xylene using ion mobility spectrometers with a radioactive and UV ionization source. |journal=Analytical Chemistry |volume=75 |issue=6 |pages=1483–90 |doi=10.1021/ac020342i |pmid=12659213}}</ref> and gasoline [[Exhaust gas|exhaust]] is a health risk.<ref name="canada-2015" /> Gasoline is often used as a recreational [[inhalant]] and can be harmful or fatal when used in such a manner.<ref>{{Cite web |title=Gasoline Sniffing |url=https://www.healthychildren.org/English/ages-stages/teen/substance-abuse/Pages/Gasoline-Sniffing.aspx |access-date=2024-03-11 |website=HealthyChildren.org |date=28 December 2012 |language=en |archive-date=11 March 2024 |archive-url=https://web.archive.org/web/20240311180622/https://www.healthychildren.org/English/ages-stages/teen/substance-abuse/Pages/Gasoline-Sniffing.aspx |url-status=live }}</ref> When burned, {{Convert|1|l|U.S.gal|sp=us|spell=in}} of gasoline emits about {{Convert|2.3|kg|lb}} of {{CO2|link=yes}}, a [[greenhouse gas]], contributing to [[human-caused climate change]].<ref>{{Cite web |date=7 March 2008 |title=Releases or emission of CO2 per Liter of fuel (Gasoline, Diesel, LPG) |url=https://www.econology.info/Emissions-co2-liter-fuel-gasoline-or-diesel-gpl/ |url-status=live |archive-url=https://web.archive.org/web/20210801054030/https://www.econology.info/Emissions-co2-liter-fuel-gasoline-or-diesel-gpl/ |archive-date=1 August 2021 |access-date=30 July 2021}}</ref><ref>{{cite journal |title=Global Climate Change: Vital Signs of the Planet |url=https://climate.nasa.gov/ |url-status=live |publisher=NASA |doi=10.1088/1748-9326/8/2/024024 |bibcode=2013ERL.....8b4024C |s2cid=250675802 |archive-url=https://web.archive.org/web/20190411121502/https://iopscience.iop.org/article/10.1088/1748-9326/8/2/024024 |archive-date=11 April 2019 |access-date=16 September 2021|last1=Cook |first1=John |last2=Nuccitelli |first2=Dana |last3=Green |first3=Sarah A. |last4=Richardson |first4=Mark |last5=Winkler |first5=Bärbel |last6=Painting |first6=Rob |last7=Way |first7=Robert |last8=Jacobs |first8=Peter |last9=Skuce |first9=Andrew |journal=Environmental Research Letters |year=2013 |volume=8 |issue=2 |page=024024 |doi-access=free }}</ref> Oil products, including gasoline, were responsible for about 32% of {{CO2}} emissions worldwide in 2021.<ref>{{cite journal |last1=Ritchie |first1=Hannah |author1-link=Hannah Ritchie |last2=Roser |first2=Max |author2-link=Max Roser |last3=Rosado |first3=Pablo |title=CO₂ and Greenhouse Gas Emissions |url=https://ourworldindata.org/co2-and-greenhouse-gas-emissions |journal=Our World in Data |date=11 May 2020 |publisher=Global Change Data Lab |access-date=19 April 2023 |archive-date=19 April 2023 |archive-url=https://web.archive.org/web/20230419090919/https://ourworldindata.org/co2-and-greenhouse-gas-emissions |url-status=live }}</ref>

===Carbon dioxide===
About {{convert|19.64|lb/U.S.gal|kg/L|sp=us|order=flip}} of [[carbon dioxide]] (CO<sub>2</sub>) are produced from burning gasoline that does not contain ethanol.<ref name="US Energy Information Administration2" /> Most of the retail gasoline now sold in the U.S. contains about 10 percent fuel ethanol (or E10) by volume.<ref name="US Energy Information Administration2" /> Burning E10 produces about {{convert|17.68|lb/U.S.gal|kg/L|sp=us|order=flip}} of CO<sub>2</sub> that is emitted from the fossil fuel content. If the CO<sub>2</sub> emissions from ethanol combustion are considered, then about {{convert|18.95|lb/U.S.gal|kg/L|sp=us|order=flip}} of CO<sub>2</sub> are produced when E10 is combusted.<ref name="US Energy Information Administration2" />

Worldwide 7 liters of gasoline are burnt for every 100&nbsp;km driven by [[cars]] and vans.<ref name="IEA 2021">{{Cite web |date=November 2021 |title=Fuel Consumption of Cars and Vans – Analysis |url=https://www.iea.org/reports/global-fuel-economy-initiative-2021/executive-summary |website=IEA |language=en-GB |archive-url=https://web.archive.org/web/20220503043712/https://www.iea.org/reports/fuel-consumption-of-cars-and-vans |archive-date=3 May 2022}}</ref>

In 2021, the [[International Energy Agency]] stated, "To ensure fuel economy and CO2 emissions standards are effective, governments must continue regulatory efforts to monitor and reduce the gap between real-world fuel economy and rated performance."<ref name="IEA 2021" />

===Contamination of soil and water===
Gasoline enters the environment through the soil, groundwater, surface water, and air. Therefore, humans may be exposed to gasoline through methods such as breathing, eating, and skin contact. For example, using gasoline-filled equipment, such as lawnmowers, drinking gasoline-contaminated water close to gasoline spills or leaks to the soil, working at a gasoline station, inhaling gasoline volatile gas when refueling at a gasoline station is the easiest way to be exposed to gasoline.<ref>{{Cite web |title=Gasoline, Automotive {{!}} ToxFAQs™ {{!}} ATSDR |url=https://wwwn.cdc.gov/TSP/ToxFAQs/ToxFAQsDetails.aspx?faqid=467&toxid=83 |url-status=live |archive-url=https://web.archive.org/web/20211212225136/https://wwwn.cdc.gov/TSP/ToxFAQs/ToxFAQsDetails.aspx?faqid=467&toxid=83 |archive-date=12 December 2021 |access-date=2021-12-12 |website=wwwn.cdc.gov}}</ref>

==Use and pricing==
{{Main|Gasoline and diesel usage and pricing|Peak oil}}The [[International Energy Agency]] said in 2021 that "road fuels should be taxed at a rate that reflects their impact on people's health and the climate".<ref name="IEA 2021"/>

===Europe===
Countries in Europe impose substantially higher [[Fuel tax|taxes]] on fuels such as gasoline when compared to the U.S. The price of gasoline in Europe is typically higher than that in the U.S. due to this difference.<ref>{{Cite journal |date=August 2011 |title=Fuel Prices and New Vehicle Fuel Economy in Europe |url=https://core.ac.uk/download/pdf/4430849.pdf |url-status=live |journal=MIT Center for Energy and Environmental Policy Research |archive-url=https://web.archive.org/web/20201113231114/https://core.ac.uk/download/pdf/4430849.pdf |archive-date=13 November 2020 |access-date=20 April 2020}}</ref>

=== U.S. ===
{{update section|date=April 2016}}
[[File:USRegularGasolinePricesUpto2019.png|thumb|U.S. Regular Gasoline Prices through 2018]]
[[File:RBOB Gasoline Prices.webp|thumb|right|300px|{{center|[[Reformulated Blendstock for Oxygenate Blending|RBOB Gasoline Prices]]}} [[Reformulated Blendstock for Oxygenate Blending|RBOB]] plus [[Fuel taxes in the United States|excise taxes on gasoline]] reflect prices paid at the pump]]
From 1998 to 2004, the price of gasoline fluctuated between {{convert|1|and|2|$/U.S.gal|sp=us|order=flip|$/l}}.<ref name="FE.gov2">{{cite web |title=Gas Prices: Frequently Asked Questions |url=http://www.fueleconomy.gov/feg/gasprices/faq.shtml#History |url-status=dead |archive-url=https://web.archive.org/web/20110121193757/http://fueleconomy.gov/feg/gasprices/FAQ.shtml#History |archive-date=21 January 2011 |access-date=16 August 2009 |work=fueleconomy.gov |df=dmy-all}}</ref> After 2004, the price increased until the average gasoline price reached a high of {{Convert|4.11|$/U.S.gal|$/l|sp=us|order=flip}} in mid-2008 but receded to approximately {{Convert|2.60|$/U.S.gal|$/l|sp=us|order=flip}} by September 2009.<ref name="FE.gov2" /> The U.S. experienced an upswing in gasoline prices through 2011,<ref name="taxfoundation.org2">{{cite web |title=Fiscal Facts |url=http://www.taxfoundation.org/UserFiles/Image/Fiscal%20Facts/gas-tax-690px.jpg |url-status=dead |archive-url=https://web.archive.org/web/20090706073258/http://www.taxfoundation.org/UserFiles/Image/Fiscal%20Facts/gas-tax-690px.jpg |archive-date=6 July 2009 |access-date=12 June 2009 }}</ref> and, by 1 March 2012, the national average was {{Convert|3.74|$/U.S.gal|$/l|sp=us|order=flip}}. California prices are higher because the California government mandates unique California gasoline formulas and taxes.<ref>{{Cite web |title=Regional gasoline price differences - U.S. Energy Information Administration (EIA) |url=https://www.eia.gov/energyexplained/gasoline/regional-price-differences.php |url-status=live |archive-url=https://web.archive.org/web/20211115150945/https://www.eia.gov/energyexplained/gasoline/regional-price-differences.php |archive-date=15 November 2021 |access-date=15 November 2021}}</ref>

In the U.S., most consumer goods bear pre-tax prices, but gasoline prices are posted with taxes included. Taxes are added by federal, state, and local governments. {{As of|2009}}, the federal tax was {{Convert|0.184|$/U.S.gal|$/l|sp=us|order=flip}} for gasoline and {{Convert|0.244|$/U.S.gal|$/l|sp=us|order=flip}} for [[Diesel fuel|diesel]] (excluding [[red diesel]]).<ref>{{cite web |title=When did the Federal Government begin collecting the gas tax?—Ask the Rambler — Highway History |url=https://www.fhwa.dot.gov/infrastructure/gastax.cfm |url-status=live |archive-url=https://web.archive.org/web/20100529003035/http://www.fhwa.dot.gov/infrastructure/gastax.cfm |archive-date=29 May 2010 |access-date=17 October 2010 |publisher=FHWA |df=dmy-all}}</ref>

About nine percent of all gasoline sold in the U.S. in May 2009 was premium grade, according to the Energy Information Administration. ''[[Consumer Reports]]'' magazine says, "If [your owner's manual] says to use regular fuel, do so—there's no advantage to a higher grade."<ref>{{cite web |title=New & Used Car Reviews & Ratings |url=http://www.consumerreports.org/cro/cars/tires-auto-parts/car-maintenance/save-at-the-pump/overview/save-at-the-pump-ov.htm |url-status=live |archive-url=https://web.archive.org/web/20130223032546/http://www.consumerreports.org/cro/cars/tires-auto-parts/car-maintenance/save-at-the-pump/overview/save-at-the-pump-ov.htm |archive-date=23 February 2013 |work=Consumer Reports |df=dmy-all}}</ref> The ''Associated Press'' said premium gas—which has a higher octane rating and costs more per gallon than regular unleaded—should be used only if the manufacturer says it is "required".<ref>{{cite web |date=19 August 2009 |title=Gassing up with premium probably a waste |url=http://www.philly.com/philly/business/personal_finance/081909_premium_gas.html |url-status=dead |archive-url=https://web.archive.org/web/20090821162543/http://www.philly.com/philly/business/personal_finance/081909_premium_gas.html |archive-date=21 August 2009 |work=philly.com}}</ref> Cars with [[Turbocharger|turbocharged]] engines and high compression ratios often specify premium gasoline because higher octane fuels reduce the incidence of "knock", or fuel pre-detonation.<ref>{{cite web |last=Biello |first=David |title=Fact or Fiction?: Premium Gasoline Delivers Premium Benefits to Your Car |url=http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-premium-g |url-status=live |archive-url=https://web.archive.org/web/20121012015036/http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-premium-g |archive-date=12 October 2012 |work=Scientific American |df=dmy-all}}</ref> The price of gasoline varies considerably between the summer and winter months.<ref>{{cite web |date=6 June 2008 |title=Why is summer fuel more expensive than winter fuel? |url=http://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/summer-fuel.htm |url-status=dead |archive-url=https://web.archive.org/web/20150530115419/http://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/summer-fuel.htm |archive-date=30 May 2015 |access-date=30 May 2015 |publisher=[[HowStuffWorks]] |df=dmy-all}}</ref>

There is a considerable difference between summer oil and winter oil in gasoline vapor pressure (Reid Vapor Pressure, RVP), which is a measure of how easily the fuel evaporates at a given temperature. The higher the gasoline volatility (the higher the RVP), the easier it is to evaporate. The conversion between the two fuels occurs twice a year, once in autumn (winter mix) and the other in spring (summer mix). The winter blended fuel has a higher RVP because the fuel must be able to evaporate at a low temperature for the engine to run normally. If the RVP is too low on a cold day, the vehicle will be difficult to start; however, the summer blended gasoline has a lower RVP. It prevents excessive evaporation when the outdoor temperature rises, reduces ozone emissions, and reduces smog levels. At the same time, vapor lock is less likely to occur in hot weather.<ref>{{Cite web |date=2008-06-06 |title=Why Is Gas More Expensive in the Summer Than in the Winter? |url=https://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/summer-fuel.htm |url-status=live |archive-url=https://web.archive.org/web/20211024171528/https://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/summer-fuel.htm |archive-date=24 October 2021 |access-date=2021-10-13 |website=HowStuffWorks |language=en}}</ref>

==Gasoline production by country==
{| class="wikitable sortable"
|+Gasoline production (per day; 2014)<ref>{{cite web |title=Gasoline production - Country rankings |url=https://www.theglobaleconomy.com/rankings/gasoline_production/ |url-status=live |archive-url=https://web.archive.org/web/20200922202533/https://www.theglobaleconomy.com/rankings/gasoline_production/ |archive-date=22 September 2020 |access-date=7 March 2019}}</ref>
! rowspan=2 | Country
! colspan=4 | Gasoline production
|-
! Barrels<br><small>(thousands)</small> !! m<sup>3</sup><br><small>(thousands)</small> !! ft<sup>3</sup><br><small>(thousands)</small> !! kL
|-
! U.S.
| {{convert|8921|oilbbl|m3 cuft kL|disp=table}}
|-
! China
| {{convert|2578|oilbbl|m3 cuft kL|disp=table}}
|-
! Japan
| {{convert|920|oilbbl|m3 cuft kL|disp=table}}
|-
! Russia
| {{convert|910|oilbbl|m3 cuft kL|disp=table}}
|-
! India
| {{convert|755|oilbbl|m3 cuft kL|disp=table}}
|-
! Canada
| {{convert|671|oilbbl|m3 cuft kL|disp=table}}
|-
! Brazil
| {{convert|533|oilbbl|m3 cuft kL|disp=table}}
|-
! Germany
| {{convert|465|oilbbl|m3 cuft kL|disp=table}}
|-
! Saudi Arabia
| {{convert|441|oilbbl|m3 cuft kL|disp=table}}
|-
! Mexico
| {{convert|407|oilbbl|m3 cuft kL|disp=table}}
|-
! South Korea
| {{convert|397|oilbbl|m3 cuft kL|disp=table}}
|-
! Iran
| {{convert|382|oilbbl|m3 cuft kL|disp=table}}
|-
! UK
| {{convert|364|oilbbl|m3 cuft kL|disp=table}}
|-
! Italy
| {{convert|343|oilbbl|m3 cuft kL|disp=table}}
|-
! Venezuela
| {{convert|277|oilbbl|m3 cuft kL|disp=table}}
|-
! France
| {{convert|265|oilbbl|m3 cuft kL|disp=table}}
|-
! Singapore
| {{convert|249|oilbbl|m3 cuft kL|disp=table}}
|-
! Australia
| {{convert|241|oilbbl|m3 cuft kL|disp=table}}
|-
! Indonesia
| {{convert|230|oilbbl|m3 cuft kL|disp=table}}
|-
! Taiwan
| {{convert|174|oilbbl|m3 cuft kL|disp=table}}
|-
! Thailand
| {{convert|170|oilbbl|m3 cuft kL|disp=table}}
|-
! Spain
| {{convert|169|oilbbl|m3 cuft kL|disp=table}}
|-
! Netherlands
| {{convert|148|oilbbl|m3 cuft kL|disp=table}}
|-
! South Africa
| {{convert|135|oilbbl|m3 cuft kL|disp=table}}
|-
! Argentina
| {{convert|122|oilbbl|m3 cuft kL|disp=table}}
|-
! Sweden
| {{convert|112|oilbbl|m3 cuft kL|disp=table}}
|-
! Greece
| {{convert|108|oilbbl|m3 cuft kL|disp=table}}
|-
! Belgium
| {{convert|105|oilbbl|m3 cuft kL|disp=table}}
|-
! Malaysia
| {{convert|103|oilbbl|m3 cuft kL|disp=table}}
|-
! Finland
| {{convert|100|oilbbl|m3 cuft kL|disp=table}}
|-
! Belarus
| {{convert|92|oilbbl|m3 cuft kL|disp=table}}
|-
! Turkey
| {{convert|92|oilbbl|m3 cuft kL|disp=table}}
|-
! Colombia
| {{convert|85|oilbbl|m3 cuft kL|disp=table}}
|-
! Poland
| {{convert|83|oilbbl|m3 cuft kL|disp=table}}
|-
! Norway
| {{convert|77|oilbbl|m3 cuft kL|disp=table}}
|-
! Kazakhstan
| {{convert|71|oilbbl|m3 cuft kL|disp=table}}
|-
! Algeria
| {{convert|70|oilbbl|m3 cuft kL|disp=table}}
|-
! Romania
| {{convert|70|oilbbl|m3 cuft kL|disp=table}}
|-
! Oman
| {{convert|69|oilbbl|m3 cuft kL|disp=table}}
|-
! Egypt
| {{convert|66|oilbbl|m3 cuft kL|disp=table}}
|-
! UAE
| {{convert|66|oilbbl|m3 cuft kL|disp=table}}
|-
! Chile
| {{convert|65|oilbbl|m3 cuft kL|disp=table}}
|-
! Turkmenistan
| {{convert|61|oilbbl|m3 cuft kL|disp=table}}
|-
! Kuwait
| {{convert|57|oilbbl|m3 cuft kL|disp=table}}
|-
! Iraq
| {{convert|56|oilbbl|m3 cuft kL|disp=table}}
|-
! Vietnam
| {{convert|52|oilbbl|m3 cuft kL|disp=table}}
|-
! Lithuania
| {{convert|49|oilbbl|m3 cuft kL|disp=table}}
|-
! Denmark
| {{convert|48|oilbbl|m3 cuft kL|disp=table}}
|-
! Qatar
| {{convert|46|oilbbl|m3 cuft kL|disp=table}}
|}

==Comparison with other fuels==
{{More citations needed section|date=December 2020}}{{See also|Energy content of biofuel}}<!--Note: I modified this table because the values in SI units didn't agree with the values in British or US units. So I used another source (Oak Ridge reference), but it did not have MJ/kg, and I did not have the time to try to find accurate densities in order to convert to MJ/kg. If someone can fill in the blanks using good data, it would be useful.-->

Below is a table of the [[energy density]] (per volume) and [[specific energy]] (per mass) of various transportation fuels as compared with gasoline. In the rows with [[Higher heating value|gross]] and [[Lower heating value|net]], they are from the [[Oak Ridge National Laboratory]]'s Transportation Energy Data Book.<ref name="TEDB2">{{cite web |title=Appendix B – Transportation Energy Data Book |url=http://cta.ornl.gov/data/appendix_b.shtml |url-status=dead |archive-url=https://web.archive.org/web/20110718143536/http://cta.ornl.gov/data/appendix_b.shtml |archive-date=18 July 2011 |access-date=8 July 2011 |work=ornl.gov |df=dmy-all}}</ref>
{| class="wikitable sortable"
! rowspan=3 | Fuel type<!-- The type needs more references which specify compositions of each fuel, plus citations, to avoid vagueness in numbers. --> !! colspan=4 | Energy density !! colspan=4 | Specific energy !! rowspan=3 | [[Octane rating|RON]]
|-
! colspan=2 | Gross !! colspan=2 | Net !! colspan=2 | Gross !! colspan=2 | Net
|-
! MJ/L !! BTU{{\}}U.S. gal !! MJ/L !! BTU{{\}}U.S. gal !! MJ/kg !! BTU/lb !! MJ/kg !! BTU/lb
|-
| Gasoline || {{convert|34.8|MJ/L|BTU/U.S.gal|disp=table}} || {{convert|115400|BTU/U.S.gal|MJ/L|order=flip|disp=table}} || {{convert|44.4|MJ/kg|BTU/lb|disp=table}}<ref name="Thomas2">{{Cite web |author=George Thomas |title=Overview of Storage Development DOE Hydrogen Program |url=http://www.eere.energy.gov/hydrogenandfuelcells/pdfs/storage.pdf |url-status=dead |archive-url=https://web.archive.org/web/20070221185632/http://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/storage.pdf |archive-date=21 February 2007}}&nbsp;{{small|(99.6&nbsp;KB)}}. Livermore, California. Sandia National Laboratories. 2000.</ref> || {{convert|41.1|MJ/kg|BTU/lb|disp=table}} || 91–98
|-
| [[Autogas]] ([[Liquified petroleum gas|LPG]]){{Efn|Consisting mostly of C3 and C4 hydrocarbons}} || {{convert|26.8|MJ/L|BTU/U.S.gal|disp=table}} || || || {{convert|46|MJ/kg|BTU/lb|disp=table}} || || || 108
|-
| [[Ethanol fuel|Ethanol]] || {{convert|21.2|MJ/L|BTU/U.S.gal|disp=table}}<ref name="Thomas2" /> || {{convert|75700|BTU/U.S.gal|MJ/L|order=flip|disp=table}} || {{convert|26.8|MJ/kg|BTU/lb|disp=table}}<ref name="Thomas2" /> || {{convert|26.7|MJ/kg|BTU/lb|disp=table}} || 108.7<ref name="Fuel 89 (2010) 2713-27202">{{cite journal |last1=Eyidogan |first1=Muharrem |last2=Ozsezen |first2=Ahmet Necati |last3=Canakci |first3=Mustafa |last4=Turkcan |first4=Ali |year=2010 |title=Impact of alcohol–gasoline fuel blends on the performance and combustion characteristics of an SI engine |journal=Fuel |volume=89 |issue=10 |page=2713 |doi=10.1016/j.fuel.2010.01.032|bibcode=2010Fuel...89.2713E }}</ref><!--remove incorrect citation of 113<ref name='Texas Energy Conservation Office'>{{cite web | url = http://www.seco.cpa.state.tx.us/re_ethanol.htm | title = Ethanol | access-date =6 October 2010}}</ref>-->
|-
| [[Methanol]] || {{convert|17.9|MJ/L|BTU/U.S.gal|disp=table}} || {{convert|56600|BTU/U.S.gal|MJ/L|order=flip|disp=table}} || {{convert|22.6|MJ/kg|BTU/lb|disp=table}} || {{convert|19.9|MJ/kg|BTU/lb|disp=table}} || 123
|-
| [[Butanol fuel|Butanol]] || {{convert|29.2|MJ/L|BTU/U.S.gal|disp=table}} || || || {{convert|36.6|MJ/kg|BTU/lb|disp=table}} || || || 91–99{{Clarify|date=June 2009|reason=need specific compositions of each fuel, plus cites, to avoid vagueness in numbers; pure n-butanol only has one rating; otherwise split into two Butanol mixes}}
|-
| [[Alcohol fuel|Gasohol]] || {{convert|31.2|MJ/L|BTU/U.S.gal|disp=table}} || {{convert|112400|BTU/U.S.gal|MJ/L|order=flip|disp=table}} || || || || || 93–94{{Clarify|date=June 2009|reason=can only be one figure, cites would help}}
|-
| [[Diesel fuel|Diesel]]{{Efn|Diesel fuel is not used in a gasoline engine, so its low octane rating is not an issue; the relevant metric for diesel engines is the [[cetane number]].}} || {{convert|38.6|MJ/L|BTU/U.S.gal|disp=table}} || {{convert|128700|BTU/U.S.gal|MJ/L|order=flip|disp=table}} || {{convert|45.4|MJ/kg|BTU/lb|disp=table}} || {{convert|42.2|MJ/kg|BTU/lb|disp=table}} || 25
|-
| [[Biodiesel]] || {{convert|33.3|–|35.7|MJ/L|BTU/U.S.gal|disp=table}}<ref>{{cite web |title=Extension Forestry |url=http://www.ces.ncsu.edu/forestry/biomass/pubs/WB0008.pdf |url-status=dead |archive-url=https://web.archive.org/web/20121122142254/http://www.ces.ncsu.edu/forestry/biomass/pubs/WB0008.pdf |archive-date=22 November 2012 |publisher=North Carolina Cooperative Extension}}</ref>{{Clarify|date=June 2009|reason=need specific composition, plus cite, to avoid vagueness in numbers; otherwise remove this as uninformative}} || {{convert|117100|BTU/U.S.gal|MJ/L|order=flip|disp=table}} || || || || ||
|-
| [[Avgas]] || {{convert|33.5|MJ/L|BTU/U.S.gal|disp=table}} || {{convert|112000|BTU/U.S.gal|MJ/L|order=flip|disp=table}} || {{convert|46.8|MJ/kg|BTU/lb|disp=table}} || {{convert|43.3|MJ/kg|BTU/lb|disp=table}} ||
|-
| [[Aviation fuel#Energy content|Jet A]] || {{convert|35.1|MJ/L|BTU/U.S.gal|disp=table}} || || || {{convert|43.8|MJ/kg|BTU/lb|disp=table}} || || ||
|-
| [[Aviation fuel#Energy content|Jet B]] || {{convert|127500|BTU/U.S.gal|MJ/L|order=flip|disp=table}} || {{convert|118700|BTU/U.S.gal|MJ/L|order=flip|disp=table}} || || || || ||
|-
| [[Liquefied natural gas|LNG]] || {{convert|25.3|MJ/L|BTU/U.S.gal|disp=table}} || || || {{convert|55|MJ/kg|BTU/lb|disp=table}} || || ||
|-
| [[Liquefied petroleum gas|LPG]] || {{convert|91300|BTU/U.S.gal|MJ/L|order=flip|disp=table}} || {{convert|83500|BTU/U.S.gal|MJ/L|order=flip|disp=table}} || {{convert|46.1|MJ/kg|BTU/lb|disp=table}} || {{convert|42.3|MJ/kg|BTU/lb|disp=table}} ||
|-
| [[Compressed hydrogen|CGH<sub>2</sub>]]{{Efn|at {{convert|{{convert|20|K|C|disp=output number only}}|C|F}}}} || {{convert|10.1|MJ/L|BTU/U.S.gal|disp=table}} || {{convert|130|BTU/U.S.gal|MJ/L|order=flip|disp=table}}<ref>{{cite web |date=25 November 2005 |title=Frequently Asked Questions |url=http://www.hydrogenassociation.org/general/faqs.asp |url-status=dead |archive-url=https://web.archive.org/web/20051125094124/http://www.hydrogenassociation.org/general/faqs.asp |archive-date=25 November 2005 |publisher=The National Hydrogen Association |access-date=23 May 2008 }}</ref> || {{convert|142|MJ/kg|BTU/lb|disp=table}} || {{convert|0.506|MJ/kg|BTU/lb|disp=table}} ||
|}

==See also==
{{Portal|Energy}}Chevron published a free high-quality technical guide <u>[https://www.chevron.com/-/media/chevron/operations/documents/motor-gas-tech-review.pdf Motor Gasolines Technical Review]</u> using common language that explains gasoline production, blending, and combustion in an engine. The report covers the US and other locations globally. {{cmn|
* {{annotated link|Aviation fuel}}
* {{annotated link|Butanol fuel}} – replacement fuel for use in unmodified gasoline engines
* {{annotated link|Biogasoline}} - petrol derived from biomass such as algae
* {{annotated link|Diesel fuel}}
* {{annotated link|Filling station}}
* {{annotated link|Fuel dispenser}}
* {{annotated link|Fuel saving device}}
* {{annotated link|Gas to liquids}}
* {{annotated link|Gasoline and diesel usage and pricing}}
* {{annotated link|Gasoline gallon equivalent}}
* {{annotated link|Hydrogen fuel}}
* {{annotated link|Internal combustion engine|abbreviation=ICE}}
* {{annotated link|Jerrycan}}
* {{annotated link|List of automotive fuel retailers}}
* {{annotated link|List of gasoline additives}}
* {{annotated link|Natural-gas condensate#Drip gas}}
* {{annotated link|Synthetic gasoline}}
* {{annotated link|Octane rating}}
* {{annotated link|World oil market chronology from 2003}}
}}

== Explanatory notes ==
{{Notelist}}

==References==
{{reflist}}

===Bibliography===

{{refbegin}}
* Gold, Russell. ''The Boom: How Fracking Ignited the American Energy Revolution and Changed the World'' (Simon & Schuster, 2014).
* Yergin, Daniel. ''[[The Quest: Energy, Security, and the Remaking of the Modern World]]'' (Penguin, 2011).
* Yergin, Daniel. ''[[The Prize: The Epic Quest for Oil, Money, and Power]]'' (Buccaneer Books, 1994; latest edition: Reissue Press, 2008).
* [http://zfacts.com/p/35.html Graph of inflation-corrected historic prices, 1970–2005. Highest in 2005] {{Webarchive|url=https://web.archive.org/web/20050923171110/http://zfacts.com/p/35.html |date=23 September 2005 }}
* [https://web.archive.org/web/20070917190316/http://www.ftc.gov/bcp/edu/pubs/consumer/autos/aut12.shtm The Low-Down on High Octane Gasoline]
* [http://www.epa.gov/otaq/regs/fuels/additive/mmt_cmts.htm MMT-US EPA] {{Webarchive|url=https://web.archive.org/web/20050920000828/http://www.epa.gov/otaq/regs/fuels/additive/mmt_cmts.htm |date=20 September 2005 }}
* An [http://www.gasresources.net/Introduction.htm introduction to the modern petroleum science] {{Webarchive|url=https://web.archive.org/web/20050404212240/http://www.gasresources.net/Introduction.htm |date=4 April 2005 }}, and to the Russian-Ukrainian theory of deep, [[abiotic petroleum]] origins.
* [http://www.straightdope.com/columns/041008.html What's the difference between premium and regular gas?] {{Webarchive|url=https://web.archive.org/web/20041019020018/http://www.straightdope.com/columns/041008.html |date=19 October 2004 }} (from [[The Straight Dope]])
* [https://web.archive.org/web/20051109151831/http://www.gtz.de/en/themen/umwelt-infrastruktur/transport/10285.htm International Fuel Prices 2005] with diesel and gasoline prices of 172 countries
* [https://web.archive.org/web/20010815085245/http://tonto.eia.doe.gov/oog/info/gdu/gasdiesel.asp EIA – Gasoline and Diesel Fuel Update]
* [https://web.archive.org/web/20060614021021/http://soc.hfac.uh.edu/artman/publish/article_375.shtml World Internet News: "Big Oil Looking for Another Government Handout", April 2006.]
* [http://journeytoforever.org/biofuel_library/ethanol_motherearth/me2.html#table Durability of various plastics: Alcohols vs. Gasoline] {{Webarchive|url=https://web.archive.org/web/20041028080312/http://journeytoforever.org/biofuel_library/ethanol_motherearth/me2.html#table |date=28 October 2004 }}
* [https://web.archive.org/web/20030221233432/http://www.gasresources.net/DisposalBioClaims.htm Dismissal of the Claims of a Biological Connection for Natural petroleum.]
* [https://www.epa.gov/OMSWWW/rfgecon.htm Fuel Economy Impact Analysis of RFG] {{Webarchive|url=https://web.archive.org/web/20121022034002/http://www.epa.gov/OMSWWW/rfgecon.htm |date=22 October 2012 }} i.e. reformulated gasoline. Has lower heating value data, actual energy content is higher see [[higher heating value]]
* [https://www.sae.org/publications/technical-papers/content/430113/ A Refiner's Viewpoint on MOTOR FUEL QUALITY] {{Webarchive|url=https://web.archive.org/web/20210204235224/https://www.sae.org/publications/technical-papers/content/430113/ |date=4 February 2021 }}, 'A Refiner's Viewpoint on Motor Fuel Quality' About the fuel specs refiners can control. Holaday W, and Happel J. (SAE paper 430113, 1943).
{{refend}}

==External links==
{{Commons}}
{{Wiktionary|gasoline|gas|petrol}}
* [https://money.cnn.com/pf/features/lists/global_gasprices/ CNN/Money: Global gas prices]
* [http://www.energy.eu/#Prices EEP: European gas prices]
* [http://cta.ornl.gov/data/index.shtml Transportation Energy Data Book]
* [http://www.energysupplylogistics.com/terminals Energy Supply Logistics Searchable Directory of US Terminals]
* [http://robotpig.net/__automotive/fuel.php High octane fuel, leaded and LRP gasoline—article from robotpig.net]
* [https://www.cdc.gov/niosh/npg/npgd0299.html CDC – NIOSH Pocket Guide to Chemical Hazards]
* [https://www.buildpriceoption.com/comparison-of-regular-midgrade-and-premium-fuel/ Comparison of Regular, Midgrade, and Premium Fuel]
;Images
* ''[https://archive.org/movies/details-db.php?collection=prelinger&collectionid=19334&from=collectionSpotlight Down the Gasoline Trail]'' Handy Jam Organization, 1935 ([[Down the Gasoline Trail|Cartoon]])

{{Motor fuel}}
{{Portal bar|Ecology|Environment|Science|Renewable energy|Engineering|Aviation|Trains|Chemistry|History of science|Cars}}
{{Authority control}}

[[Category:IARC Group 1 carcinogens]]
[[Category:Inhalants]]
[[Category:Liquid fuels]]
[[Category:Petroleum products]]