Fuel oil

<h2 id="uses">Uses</h2>
 Oil has many uses; it heats homes and businesses and fuels <a href="/facts/Truck/9GMJWsQU">trucks</a>, <a href="/facts/Ship/418ptx1L">ships</a>, and some <a href="/facts/Car/I1IsH8IK">cars</a>. A small amount of <a href="/facts/Electricity/hNC8D65W">electricity</a> is produced by diesel, but it is more <a href="/facts/Pollution/JRagxumQ">polluting</a> and more expensive than <a href="/facts/Natural_gas/9MYQ7NAP">natural gas</a>. It is often used as a backup fuel for <a href="/facts/Peaking_power_plant/PQ8x2HjH">peaking power plants</a> in case the supply of natural gas is interrupted or as the main fuel for small <a href="/facts/Electrical_generator/5sATsUGX">electrical generators</a>. In Europe, the use of diesel is generally restricted to cars (about 40%), SUVs (about 90%), and trucks and buses (over 99%). The market for home heating using fuel oil has decreased due to the widespread penetration of <a href="/facts/Natural_gas/9MYQ7NAP">natural gas</a> as well as <a href="/facts/Heat_pumps/JAprSmeL">heat pumps</a>. However, it is very common in some areas, such as the <a href="/facts/Northeastern_United_States/Xa8zQlkM">Northeastern United States</a>.

<a href="/facts/Heavy_fuel_oil/GNsn71Xt">Residual fuel oil</a> is less useful because it is so <a href="/facts/Viscous/QLVfrdCz">viscous</a> that it has to be heated with a special heating system before use and it may contain relatively high amounts of <a href="/facts/Pollutant/4f9kmFzq">pollutants</a>, particularly <a href="/facts/Sulfur/IK0amTfM">sulfur</a>, which forms <a href="/facts/Sulfur_dioxide/jDK1fIDs">sulfur dioxide</a> upon combustion. However, its undesirable properties make it very cheap. In fact, it is the cheapest liquid fuel available. Since it requires heating before use, residual fuel oil cannot be used in road vehicles, <a href="/facts/Boat/dz9LnNN6">boats</a> or small ships, as the heating equipment takes up valuable space and makes the vehicle heavier. Heating the oil is also a delicate procedure, which is impractical on small, fast moving vehicles. However, <a href="/facts/Power_plant/vYeVY1fD">power plants</a> and large ships are able to use residual fuel oil.
Use of residual fuel oil was more common in the past. It powered <a href="/facts/Boiler/uPqTq0I6">boilers</a>, <a href="/facts/Railroad/9nJQbsDV">railroad</a> <a href="/facts/Steam_locomotive/cXEQwhFk">steam locomotives</a>, and <a href="/facts/Steamship/Ay0fhKBW">steamships</a>. Locomotives, however, have become powered by diesel or electric power; steamships are not as common as they were previously due to their higher operating costs (most <a href="/facts/LNG_carrier/MwSdULC1">LNG carriers</a> use steam plants, as "boil-off" gas emitted from the cargo can be used as a fuel source); and most boilers now use <a href="/facts/Heating_oil/gMSISJzS">heating oil</a> or natural gas. Some industrial boilers still use it and so do some old buildings, including in <a href="/facts/New_York_City/YlyvFmVC">New York City</a>. In 2011 New York City estimated that the 1% of its buildings that burned fuel oils No. 4 and No. 6 were responsible for 86% of the <a href="/facts/Soot/xzU91yKv">soot</a> pollution generated by all buildings in the city. New York made the phase out of these fuel grades part of its environmental plan, PlaNYC, because of concerns for the health effects caused by fine particulates,<a class="footnote-ref" id="fnref:1" href="#fn:1">1</a> and all buildings using fuel oil No. 6 had been converted to less polluting fuel by the end of 2015.<a class="footnote-ref" id="fnref:2" href="#fn:2">2</a>
Residual fuel's use in electrical generation has also decreased. In 1973, residual fuel oil produced 16.8% of the electricity in the US. By 1983, it had fallen to 6.2%, and as of 2005, electricity production from all forms of petroleum, including diesel and residual fuel, is only 3% of total production. The decline is the result of price competition with natural gas and environmental restrictions on emissions. For power plants, the costs of heating the oil, extra pollution control and additional maintenance required after burning it often outweigh the low cost of the fuel. Burning fuel oil, particularly residual fuel oil, produces uniformly higher <a href="/facts/Carbon_dioxide/xGzpppEp">carbon dioxide</a> emissions than natural gas.<a class="footnote-ref" id="fnref:3" href="#fn:3">3</a>
Heavy fuel oils continue to be used in the boiler "lighting up" facility in many coal-fired power plants. This use is approximately analogous to using kindling to start a fire. Without performing this act it is difficult to begin the large-scale combustion process.
The chief drawback to residual fuel oil is its high initial viscosity, particularly in the case of No. 6 oil, which requires a correctly engineered system for storage, pumping, and burning. Though it is still usually lighter than water (with a specific gravity usually ranging from 0.95 to 1.03) it is much heavier and more viscous than No. 2 oil, kerosene, or gasoline. No. 6 oil must, in fact, be stored at around 38 °C (100 °F) heated to 65–120 °C (149–248 °F) before it can be easily pumped, and in cooler temperatures it can congeal into a tarry semisolid. The flash point of most blends of No. 6 oil is, incidentally, about 65 °C (149 °F). Attempting to pump high-viscosity oil at low temperatures was a frequent cause of damage to fuel lines, furnaces, and related equipment which were often designed for lighter fuels.
For comparison, BS 2869 Class G heavy fuel oil behaves in similar fashion, requiring storage at 40 °C (104 °F), pumping at around 50 °C (122 °F) and finalizing for burning at around 90–120 °C (194–248 °F).
Most of the facilities which historically burned No. 6 or other residual oils were industrial plants and similar facilities constructed in the early or mid 20th century, or which had switched from coal to oil fuel during the same time period. In either case, residual oil was seen as a good prospect because it was cheap and readily available. Most of these facilities have subsequently been closed and demolished, or have replaced their fuel supplies with a simpler one such as gas or No. 2 oil. The high sulfur content of No. 6 oil—up to 3% by weight in some extreme cases—had a corrosive effect on many heating systems (which were usually designed without adequate corrosion protection in mind), shortening their lifespans and increasing the polluting effects. This was particularly the case in furnaces that were regularly shut down and allowed to go cold, because the internal condensation produced <a href="/facts/Sulfuric_acid/Wom6fymJ">sulfuric acid</a>.
Environmental cleanups at such facilities are frequently complicated by the use of <a href="/facts/Asbestos/dEnjQyee">asbestos</a> insulation on the fuel feed lines. No. 6 oil is very persistent, and does not degrade rapidly. Its viscosity and stickiness also make remediation of underground contamination very difficult, since these properties reduce the effectiveness of methods such as <a href="/facts/Air_stripping/IeKACBEK">air stripping</a>.
When released into water, such as a river or ocean, residual oil tends to break up into patches or tarballs – mixtures of oil and particulate matter such as silt and floating organic matter – rather than form a single slick. An average of about 5-10% of the material will evaporate within hours of the release, primarily the lighter hydrocarbon fractions. The remainder will then often sink to the bottom of the water column.

<h2 id="health-effects">Health effects</h2>
Because of the low quality of bunker fuel, when burnt it is especially harmful to the health of humans, causing serious illnesses and deaths. Prior to the IMO's 2020 sulfur cap, shipping industry air pollution was estimated to cause around 400,000 premature deaths each year, from lung cancer and cardiovascular disease, as well as 14 million childhood asthma cases each year.<a class="footnote-ref" id="fnref:4" href="#fn:4">4</a>
Even after the introduction of cleaner fuel rules in 2020, shipping air pollution is still estimated to account for around 250,000 deaths each year, and around 6.4 million childhood asthma cases each year.
The hardest hit countries by air pollution from ships are China, Japan, the UK, Indonesia, and Germany. In 2015, shipping air pollution killed an estimated 20,520 people in China, 4,019 people in Japan, and 3,192 people in the UK.<a class="footnote-ref" id="fnref:5" href="#fn:5">5</a>
According to an ICCT study, countries located on major shipping lanes are particularly exposed, and can see shipping account for a high percentage of overall deaths from transport sector air pollution. In Taiwan, shipping accounts for 70% of all transport-attributable air pollution deaths in 2015, followed by Morocco at 51%, Malaysia and Japan both at 41%, Vietnam at 39%, and the UK at 38%.<a class="footnote-ref" id="fnref:6" href="#fn:6">6</a>
As well as commercial shipping, cruise ships also emit large amounts of air pollution, damaging people's health. Up to 2019, it was reported that the ships of the single largest cruise company, <a href="/facts/Carnival_Corporation_%2526_plc/D1mS4cTz">Carnival Corporation & plc</a>, emitted ten times more sulfur dioxide than all of Europe's cars combined.<a class="footnote-ref" id="fnref:7" href="#fn:7">7</a>

<h2 id="general-classification">General classification</h2>
<h3>United States</h3>
Although the following trends generally hold true, different organizations may have different numerical specifications for the six fuel grades. The boiling point and <a href="/facts/Catenation/vm7k4zsv">carbon chain</a> length of the fuel increases with fuel oil number. <a href="/facts/Viscosity/QLVfrdCz">Viscosity</a> also increases with number, and the heaviest oil must be heated for it to flow. Price usually decreases as the fuel number increases.<a class="footnote-ref" id="fnref:8" href="#fn:8">8</a>
Number 1 fuel oil is a volatile distillate oil intended for vaporizing pot-type burners and high-performance/clean diesel engines.<a class="footnote-ref" id="fnref:9" href="#fn:9">9</a> It is the <a href="/facts/Kerosene/DoHPYXKp">kerosene</a> refinery cut that boils off immediately after the heavy naphtha cut used for <a href="/facts/Gasoline/lcnxq5BS">gasoline</a>. This fuel is commonly known as <a href="/facts/Diesel_fuel/lm71xc19">diesel no. 1</a>, <a href="/facts/Kerosene/DoHPYXKp">kerosene</a>, and <a href="/facts/Jet_fuel/4CDswF3t">jet fuel</a>. Former names include: coal oil, stove oil, and range oil.<a class="footnote-ref" id="fnref:10" href="#fn:10">10</a>
Number 2 fuel oil is a distillate home <a href="/facts/Heating_oil/gMSISJzS">heating oil</a>.<a class="footnote-ref" id="fnref:11" href="#fn:11">11</a> Trucks and some cars use similar <a href="/facts/Diesel_fuel/lm71xc19">diesel no. 2</a> with a <a href="/facts/Cetane_number/jzmECJhV">cetane number</a> limit describing the ignition quality of the fuel. Both are typically obtained from the light gas oil cut. The name gasoil refers to the original use of this fraction in the late 19th and early 20th centuries—the gas oil cut was used as an enriching agent for carbureted water gas <a href="/facts/Manufactured_gas/DW8H1THN">manufacture</a>.<a class="footnote-ref" id="fnref:12" href="#fn:12">12</a>
Number 3 fuel oil was a distillate oil for burners requiring low-viscosity fuel. ASTM merged this grade into the number 2 specification, and the term has been rarely used since the mid-20th century.<a class="footnote-ref" id="fnref:13" href="#fn:13">13</a>
Number 4 fuel oil is a commercial heating oil for burner installations not equipped with preheaters.<a class="footnote-ref" id="fnref:14" href="#fn:14">14</a> It may be obtained from the heavy gas oil cut.<a class="footnote-ref" id="fnref:15" href="#fn:15">15</a> This fuel is sometimes known by the Navy specification of Bunker A.
Number 5 fuel oil is a residual-type industrial heating oil requiring preheating to 77–104 °C (171–219 °F) for proper atomization at the burners.<a class="footnote-ref" id="fnref:16" href="#fn:16">16</a> It may be obtained from the heavy gas oil cut,<a class="footnote-ref" id="fnref:17" href="#fn:17">17</a> or it may be a blend of residual oil with enough number 2 oil to adjust viscosity until it can be pumped without preheating.<a class="footnote-ref" id="fnref:18" href="#fn:18">18</a> This fuel is sometimes known by the Navy specification of Bunker B.
Number 6 fuel oil is a high-viscosity residual oil requiring preheating to 104–127 °C (219–261 °F). Residual means the material remaining after the more valuable cuts of crude oil have boiled off. The residue may contain various undesirable impurities, including 2% water and 0.5% <a href="/facts/Mineral_oil/KjXl9BUo">mineral oil</a>. This fuel may be known as residual fuel oil (RFO), by the Navy specification of Bunker C, or by the Pacific Specification of PS-400.<a class="footnote-ref" id="fnref:19" href="#fn:19">19</a>

<h3>United Kingdom</h3>
The British Standard BS 2869, Fuel Oils for Agricultural, Domestic and Industrial Engines, specifies the following fuel oil classes:

Fuel oil classes per BS 2869<table><tbody><tr><th>Class</th><th>Type</th><th>Min. kinematic viscosity</th><th>Max. kinematic viscosity</th><th>Min. flash point</th><th>Max. sulfur content</th><th>Alias</th></tr><tr><td>C1</td><td>Distillate</td><td>—</td><td>—</td><td>43 °C</td><td>0.040 % (m/m)</td><td>Paraffin</td></tr><tr><td>C2</td><td>Distillate</td><td>1.000 mm2/s at 40 °C</td><td>2.000 mm2/s at 40 °C</td><td>38 °C</td><td>0.100 % (m/m)</td><td><a href="/facts/Kerosene/DoHPYXKp">Kerosene</a>, 28-second oil</td></tr><tr><td>A2</td><td>Distillate</td><td>2.000 mm2/s at 40 °C</td><td>5.000 mm2/s at 40 °C</td><td>> 55 °C</td><td>0.001 % (m/m)</td><td>low-sulfur gas oil, <a href="/facts/Ultra-low-sulfur_diesel/TedIPWwz">ULSD</a></td></tr><tr><td>D</td><td>Distillate</td><td>2.000 mm2/s at 40 °C</td><td>5.000 mm2/s at 40 °C</td><td>> 55 °C</td><td>0.100 % (m/m)</td><td>Gas oil, <a href="/facts/Red_diesel/Wak4jfjD">red diesel</a>, 35-second oil</td></tr><tr><td>E</td><td>Residual</td><td>—</td><td>8.200 mm2/s at 100 °C</td><td>66 °C</td><td>1.000 % (m/m)</td><td>Light fuel oil, LFO, 250-second oil</td></tr><tr><td>F</td><td>Residual</td><td>8.201 mm2/s at 100 °C</td><td>20.000 mm2/s at 100 °C</td><td>66 °C</td><td>1.000 % (m/m)</td><td>Medium fuel oil, MFO, 1000-second oil</td></tr><tr><td>G</td><td>Residual</td><td>20.010 mm2/s at 100 °C</td><td>40.000 mm2/s at 100 °C</td><td>66 °C</td><td>1.000 % (m/m)</td><td>Heavy fuel oil, HFO, 3500-second oil</td></tr><tr><td>H</td><td>Residual</td><td>40.010 mm2/s at 100 °C</td><td>56.000 mm2/s at 100 °C</td><td>66 °C</td><td>1.000 % (m/m)</td><td>—</td></tr></tbody></table>
Class C1 and C2 fuels are kerosene-type fuels. C1 is for use in flueless appliances (e.g. <a href="/facts/Kerosene_lamp/tFBCrVm5">lamps</a>). C2 is for vaporizing or atomizing burners in appliances connected to flues.
Class A2 fuel is suitable for mobile, <a href="/facts/Non-road_engine/XJWqttPb">off-road applications</a> that are required to use a <a href="/facts/Ultra-low-sulfur_diesel/TedIPWwz">sulfur-free fuel</a>. Class D fuel is similar to Class A2 and is suitable for use in stationary applications, such as domestic, commercial, and industrial heating. The BS 2869 standard permits Class A2 and Class D fuel to contain up to 7% (V/V) <a href="/facts/Biodiesel/M6FkfJXH">biodiesel</a> (<a href="/facts/Fatty_acid_methyl_ester/q3fUpu56">fatty acid methyl ester</a>, FAME), provided the FAME content meets the requirements of the BS EN 14214 standard.
Classes E to H are residual oils for atomizing burners serving boilers or, with the exception of Class H, certain types of larger combustion engines. Classes F to H invariably require heating prior to use; Class E fuel may require preheating, depending on ambient conditions.

<h3>Russia</h3>
<a href="/facts/Mazut/3cA1UFn2">Mazut</a> is a residual fuel oil often derived from Russian petroleum sources and is either blended with lighter petroleum fractions or burned directly in specialized boilers and furnaces. It is also used as a petrochemical feedstock. In the Russian practice, though, "mazut" is an umbrella term roughly synonymous with the fuel oil in general, that covers most of the types mentioned above, except US grades 1 and 2/3, for which separate terms exist (<a href="/facts/Kerosene/DoHPYXKp">kerosene</a> and <a href="/facts/Diesel_fuel/lm71xc19">diesel fuel</a>/solar oil respectively — Russian practice doesn't differentiate between diesel fuel and heating oil). This is further separated in two grades, "naval mazut" being analogous to US grades 4 and 5, and "furnace mazut", a heaviest residual fraction of the crude, almost exactly corresponding to US Number 6 fuel oil and further graded by viscosity and sulfur content.

<h2 id="maritime-fuel-classification">Maritime fuel classification</h2>
In the <a href="/facts/Shipping/0wYezNsU">maritime</a> field another type of classification is used for fuel oils:

<ul><li>MGO (Marine gas oil) - Roughly equivalent to no. 2 fuel oil, made from distillate only</li>
<li>MDO (<a href="/facts/Marine_diesel_oil/IvC5AFry">Marine diesel oil</a>) - Roughly equivalent to no. 3 fuel oil, a blend of heavy gasoil that may contain very small amounts of black refinery feed stocks, but has a low viscosity up to 12 cSt so it need not be heated for use in internal combustion engines</li>
<li>IFO (Intermediate fuel oil) - Roughly equivalent no. 4 fuel oil, a blend of gasoil and heavy fuel oil, with less gasoil than marine diesel oil</li>
<li>HFO (Heavy fuel oil) - Pure or nearly pure residual oil, roughly equivalent to no. 5 and no. 6 fuel oil</li>
<li>NSFO (Navy special fuel oil) - Another name for no. 5 HFO</li>
<li>MFO (Marine fuel oil) - Another name for no. 6 HFO</li></ul>
Marine diesel oil contains some heavy fuel oil, unlike regular diesels.

<h3>Standards and classification</h3>
<a href="/facts/Calculated_Carbon_Aromaticity_Index/bgYduTYl">CCAI</a> and <a href="/facts/Calculated_Ignition_Index/FJxXGm9f">CII</a> are two indexes which describe the ignition quality of residual fuel oil, and CCAI is especially often calculated for marine fuels. Despite this, marine fuels are still quoted on the international bunker markets with their maximum viscosity (which is set by the ISO 8217 standard - see below) due to the fact that marine engines are designed to use different viscosities of fuel.<a class="footnote-ref" id="fnref:20" href="#fn:20">20</a> The unit of viscosity used is the <a href="/facts/Centistoke/QLVfrdCz">centistoke</a> (cSt) and the fuels most frequently quoted are listed below in order of cost, the least expensive first.

<ul><li>IFO 380 - Intermediate fuel oil with a maximum viscosity of 380 centistokes (<3.5% sulfur)</li>
<li>IFO 180 - Intermediate fuel oil with a maximum viscosity of 180 centistokes (<3.5% sulfur)</li>
<li>LS 380 - Low-sulfur (<1.0%) intermediate fuel oil with a maximum viscosity of 380 centistokes</li>
<li>LS 180 - Low-sulfur (<1.0%) intermediate fuel oil with a maximum viscosity of 180 centistokes</li>
<li>MDO - Marine diesel oil</li>
<li>MGO - Marine gasoil</li>
<li>LSMGO - Low-sulfur (<0.1%) Marine Gas Oil - The fuel is to be used in EU Ports and Anchorages. EU Sulfur directive 2005/33/EC</li>
<li>ULSMGO - Ultra-Low-Sulfur Marine Gas Oil - referred to as Ultra-Low-Sulfur Diesel (sulfur 0.0015% max) in the US and Auto Gas Oil (sulfur 0.001% max) in the EU. Maximum sulfur allowable in US territories and territorial waters (inland, marine, and automotive) and in the EU for inland use.</li></ul>
The <a href="/facts/Density/92p6hh9I">density</a> is also an important parameter for fuel oils since marine fuels are purified before use to remove water and dirt from the oil. Since the purifiers use <a href="/facts/Centrifugal_force/CWgvMw6w">centrifugal force</a>, the oil must have a density which is sufficiently different from water. Older purifiers work with a fuel having a maximum of 991 kg/m3; with modern purifiers it is also possible to purify oil with a density of 1010 kg/m3.
The first British standard for fuel oil came in 1982. The latest standard is ISO 8217 issued in 2017.<a class="footnote-ref" id="fnref:21" href="#fn:21">21</a> The ISO standard describe four qualities of distillate fuels and 10 qualities of residual fuels. Over the years the standards have become stricter on environmentally important parameters such as sulfur content. The latest standard also banned the adding of used lubricating oil (ULO).
Some parameters of marine fuel oils according to ISO 8217 (3. ed 2005):

<table><tbody><tr><th colspan="7">Marine distillate fuels</th></tr><tr><th>Parameter</th><th>Unit</th><th>Limit</th><th>DMX</th><th>DMA</th><th>DMB</th><th>DMC</th></tr><tr><td>Density at 15 °C</td><td>kg/m3</td><td>Max</td><td>-</td><td>890.0</td><td>900.0</td><td>920.0</td></tr><tr><td>Viscosity at 40 °C</td><td>mm2/s</td><td>Max</td><td>5.5</td><td>6.0</td><td>11.0</td><td>14.0</td></tr><tr><td></td><td>mm2/s</td><td>Min</td><td>1.4</td><td>1.5</td><td>-</td><td>-</td></tr><tr><td>Water</td><td>% V/V</td><td>Max</td><td>-</td><td>-</td><td>0.3</td><td>0.3</td></tr><tr><td>Sulfur1</td><td>% (m/m)</td><td>Max</td><td>1.0</td><td>1.5</td><td>2.0</td><td>2.0</td></tr><tr><td>Aluminium + Silicon2</td><td>mg/kg</td><td>Max</td><td>-</td><td>-</td><td>-</td><td>25</td></tr><tr><td><a href="/facts/Flash_point/97JQP35E">Flash point</a>3</td><td>°C</td><td>Min</td><td>43</td><td>60</td><td>60</td><td>60</td></tr><tr><td><a href="/facts/Pour_point/yxz8lpBf">Pour point</a>, Summer</td><td>°C</td><td>Max</td><td>-</td><td>0</td><td>6</td><td>6</td></tr><tr><td>Pour point, Winter</td><td>°C</td><td>Max</td><td>-</td><td>-6</td><td>0</td><td>0</td></tr><tr><td><a href="/facts/Cloud_point/LXVSsucF">Cloud point</a></td><td>°C</td><td>Max</td><td>-16</td><td>-</td><td>-</td><td>-</td></tr><tr><td>Calculated Cetane Index</td><td></td><td>Min</td><td>45</td><td>40</td><td>35</td><td>-</td></tr></tbody></table>
<table><tbody><tr><th colspan="13">Marine residual fuels</th></tr><tr><th>Parameter</th><th>Unit</th><th>Limit</th><th>RMA 30</th><th>RMB 30</th><th>RMD 80</th><th>RME 180</th><th>RMF 180</th><th>RMG 380</th><th>RMH 380</th><th>RMK 380</th><th>RMH 700</th><th>RMK 700</th></tr><tr><td>Density at 15 °C</td><td>kg/m3</td><td>Max</td><td>960.0</td><td>975.0</td><td>980.0</td><td>991.0</td><td>991.0</td><td>991.0</td><td>991.0</td><td>1010.0</td><td>991.0</td><td>1010.0</td></tr><tr><td>Viscosity at 50 °C</td><td>mm2/s</td><td>Max</td><td>30.0</td><td>30.0</td><td>80.0</td><td>180.0</td><td>180.0</td><td>380.0</td><td>380.0</td><td>380.0</td><td>700.0</td><td>700.0</td></tr><tr><td>Water</td><td>% V/V</td><td>Max</td><td>0.5</td><td>0.5</td><td>0.5</td><td>0.5</td><td>0.5</td><td>0.5</td><td>0.5</td><td>0.5</td><td>0.5</td><td>0.5</td></tr><tr><td>Sulfur1</td><td>% (m/m)</td><td>Max</td><td>3.5</td><td>3.5</td><td>3.5</td><td>3.5</td><td>3.5</td><td>3.5</td><td>3.5</td><td>3.5</td><td>3.5</td><td>3.5</td></tr><tr><td>Aluminium + Silicon2</td><td>mg/kg</td><td>Max</td><td>80</td><td>80</td><td>80</td><td>80</td><td>80</td><td>80</td><td>80</td><td>80</td><td>80</td><td>80</td></tr><tr><td><a href="/facts/Flash_point/97JQP35E">Flash point</a>3</td><td>°C</td><td>Min</td><td>60</td><td>60</td><td>60</td><td>60</td><td>60</td><td>60</td><td>60</td><td>60</td><td>60</td><td>60</td></tr><tr><td><a href="/facts/Pour_point/yxz8lpBf">Pour point</a>, Summer</td><td>°C</td><td>Max</td><td>6</td><td>24</td><td>30</td><td>30</td><td>30</td><td>30</td><td>30</td><td>30</td><td>30</td><td>30</td></tr><tr><td>Pour point, Winter</td><td>°C</td><td>Max</td><td>0</td><td>24</td><td>30</td><td>30</td><td>30</td><td>30</td><td>30</td><td>30</td><td>30</td><td>30</td></tr></tbody></table>
<ol><li>Maximum sulfur content in the open ocean is 0.5% since January 2020.<a class="footnote-ref" id="fnref:22" href="#fn:22">22</a> Maximum sulfur content in designated areas is 0.1% since 1 January 2015. Before then it was 1.00%.</li>
<li>The content of aluminum and silicon is limited because those metals are dangerous for the engine. Those elements are present because some components of the fuel are manufactured with Fluid Catalytic Cracking process, which makes use of catalyst containing aluminum and silicon.</li>
<li>The flash point of all fuels used in the engine room should be at least 60 °C. (DMX is used for things like emergency generators and not normally used in the engine room. Gaseous fuels such as LPG/LNG have special class rules applied to the fuel systems.)</li></ol>
<h3>Bunker fuel</h3>
Main article: <a href="/facts/Heavy_fuel_oil/GNsn71Xt">Heavy fuel oil</a>

Bunker fuel or bunker crude is technically any type of fuel oil used aboard <a href="/facts/Watercraft/XX8YawP1">water vessels</a>. Its name is derived from coal bunkers, where the fuel was originally stored. In 2019, large ships consumed 213 million metric tons of bunker fuel.<a class="footnote-ref" id="fnref:23" href="#fn:23">23</a> The Australian Customs and the Australian Tax Office defines a bunker fuel as the fuel that powers the engine of a ship or aircraft. Bunker A is No. 4 fuel oil, bunker B is No. 5, and bunker C is No. 6. Since No. 6 is the most common, "bunker fuel" is often used as a synonym for No. 6. No. 5 fuel oil is also called Navy Special Fuel Oil (NSFO) or just navy special; No. 5 or 6 are also commonly called heavy fuel oil (HFO) or furnace fuel oil (FFO); the high viscosity requires heating, usually by a recirculated low pressure <a href="/facts/Steam/RDGCdmzT">steam</a> system, before the oil can be pumped from a bunker tank. Bunkers are rarely labeled this way in modern maritime practice.
Since the 1980s the <a href="/facts/International_Organization_for_Standardization/IacYR7Yg">International Organization for Standardization</a> (ISO) has been the accepted standard for marine fuels (bunkers). The standard is listed under number 8217, with recent updates in 2010 and 2017. The latest edition of bunker fuel specification is ISO 8217: 2017. The standard divides fuels into residual and distillate fuels. The most common residual fuels in the shipping industry are RMG and RMK.<a class="footnote-ref" id="fnref:24" href="#fn:24">24</a> The differences between the two are mainly the density and viscosity, with RMG generally being delivered at 380 <a href="/facts/Viscosity/QLVfrdCz">centistokes</a> or less, and RMK at 700 centistokes or less. Ships with more advanced engines can process heavier, more viscous, and thus cheaper, fuel. Governing bodies around the world, e.g., California, European Union, have established Emission Control Areas (ECA) that limit the maximum sulfur of fuels burned in their ports to limit pollution, reducing the percentage of sulfur and other particulates from 4.5% m/m to as little as 0.10% as of 2015 inside an ECA. As of 2013 3.5% continued to be permitted outside an ECA, but the International Maritime Organization has planned to lower the sulfur content requirement outside the ECAs to 0.5% m/m by 2020.<a class="footnote-ref" id="fnref:25" href="#fn:25">25</a> This is where Marine Distillate Fuels and other alternatives<a class="footnote-ref" id="fnref:26" href="#fn:26">26</a> to use of heavy bunker fuel come into play. They have similar properties to diesel #2, which is used as road diesel around the world. The most common grades used in shipping are DMA and DMB.<a class="footnote-ref" id="fnref:27" href="#fn:27">27</a> <a href="/facts/Greenhouse_gas/HXaHqrT8">Greenhouse gas</a> emissions resulting from the use of international bunker fuels are currently included in national inventories.<a class="footnote-ref" id="fnref:28" href="#fn:28">28</a><a class="footnote-ref" id="fnref:29" href="#fn:29">29</a>

Table of fuel oils<table><tbody><tr><th>Name</th><th>Alias</th><th>Alias</th><th>Alias</th><th>Alias</th><th>Alias</th><th>Type</th><th>Chain length</th></tr><tr><td>No. 1 fuel oil</td><td>No. 1 distillate</td><td>No. 1 diesel fuel</td><td><a href="/facts/Kerosene/DoHPYXKp">Kerosene</a></td><td><a href="/facts/Jet_fuel/4CDswF3t">Jet fuel</a></td><td></td><td>Distillate</td><td>9-16</td></tr><tr><td>No. 2 fuel oil</td><td>No. 2 distillate</td><td>No. 2 <a href="/facts/Diesel_fuel/lm71xc19">diesel fuel</a></td><td>Road diesel</td><td>Rail diesel</td><td>Marine gas oil</td><td>Distillate</td><td>10-20</td></tr><tr><td>No. 3 fuel oil</td><td>No. 3 distillate</td><td>No. 3 diesel fuel</td><td>Marine diesel oil</td><td></td><td></td><td>Distillate</td><td></td></tr><tr><td>No. 4 fuel oil</td><td>No. 4 distillate</td><td>No. 4 residual fuel oil</td><td>Bunker A</td><td>Intermediate fuel oil</td><td></td><td>Distillate/Residual</td><td>12-70</td></tr><tr><td>No. 5 fuel oil</td><td>No. 5 residual fuel oil</td><td>Heavy fuel oil</td><td>Bunker B</td><td>Navy special fuel oil</td><td>Furnace fuel oil</td><td>Residual</td><td>12-70</td></tr><tr><td>No. 6 fuel oil</td><td>No. 6 residual fuel oil</td><td>Heavy fuel oil</td><td>Bunker C</td><td>Marine fuel oil</td><td>Furnace fuel oil</td><td>Residual</td><td>20-70</td></tr></tbody></table>
Heavy fuel oil is still the primary fuel for <a href="/facts/Cruise_ship/PzQCcICA">cruise ships</a>, a tourism sector that is associated with a clean and friendly image. In stark contrast, the <a href="/facts/Exhaust_gas/kLpq1eUX">exhaust gas</a> emissions - due to HFO's high sulfur content - result in an eco balance significantly worse than that for individual mobility.<a class="footnote-ref" id="fnref:30" href="#fn:30">30</a><a class="footnote-ref" id="fnref:31" href="#fn:31">31</a><a class="footnote-ref" id="fnref:32" href="#fn:32">32</a>

<h2 id="bunkering">Bunkering</h2>
The term "<a href="/facts/Bunkering/ERJSFQxn">bunkering</a>" broadly relates to storage of petroleum products in tanks (among other, disparate meanings). The precise meaning can be further specialized depending on context. Perhaps the most common, more specialized usage refers to the practice and business of refueling ships. Bunkering operations are located at seaports, and they include the storage of bunker (ship) fuels and the provision of the fuel to vessels.<a class="footnote-ref" id="fnref:33" href="#fn:33">33</a>
Alternatively "bunkering" may apply to the shipboard logistics of loading fuel and distributing it among available bunkers (on-board fuel tanks).<a class="footnote-ref" id="fnref:34" href="#fn:34">34</a>
Finally, in the context of the <a href="/facts/Petroleum_industry_in_Nigeria/D0N9cvWN">oil industry</a> in <a href="/facts/Nigeria/gbW17BX8">Nigeria</a>, bunkering<a class="footnote-ref" id="fnref:35" href="#fn:35">35</a> has come to refer to the <a href="/facts/Oil_theft_in_Nigeria/y9w7K2K7">illegal diversion of crude oil</a> (often subsequently refined in makeshift facilities into lighter transportation fuels) by the unauthorized cutting of holes into transport pipelines, often by very crude and hazardous means and causing <a href="/facts/Petroleum_industry_in_Nigeria/D0N9cvWN">spills</a>.
As of 2018, some 300 million metric tons of fuel oil is used for ship bunkering. On January 1, 2020, regulations set by the International Marine Organization (IMO) all marine shipping vessels will require the use of very low sulfur fuel oil (0.5% Sulfur) or to install <a href="/facts/Flue-gas_desulfurization/J6IBX70D">exhaust gas scrubber</a> systems to remove the excess sulfur dioxide. The emissions from ships have generally been controlled by the following sulfur caps on any fuel oil used on board: 3.50% on and after 1 January 2012 and 0.50% on and after 1 January 2020.<a class="footnote-ref" id="fnref:36" href="#fn:36">36</a>
Further removal of sulfur translates to additional energy and capital costs<a class="footnote-ref" id="fnref:37" href="#fn:37">37</a> and can impact fuel price and availability. If priced correctly the excess cheap yet dirty fuel would find its way into other markets, including displacing some onshore energy production in nations with low environmental protection .<a class="footnote-ref" id="fnref:38" href="#fn:38">38</a>

<h2 id="transportation">Transportation</h2>
Fuel oil is transported worldwide by fleets of <a href="/facts/Oil_tanker/WHUhISVB">oil tankers</a> making deliveries to suitably sized strategic ports such as <a href="/facts/Houston/1v8AwQUN">Houston</a>, US; <a href="/facts/Singapore/CQDkhUvD">Singapore</a>; <a href="/facts/Fujairah/aVhsCAoD">Fujairah</a>, <a href="/facts/United_Arab_Emirates/o1bEjgbR">United Arab Emirates</a>; <a href="/facts/Balboa%2c_Panama/pzUKWKc1">Balboa, Panama</a>, <a href="/facts/Crist%25C3%25B3bal%2c_Col%25C3%25B3n/1LbqxT3S">Cristobal</a>, Panama; Sakha, <a href="/facts/Egypt/8Ttg0JwB">Egypt</a>; <a href="/facts/Algeciras/wnRuKJkP">Algeciras</a>, Spain and <a href="/facts/Rotterdam/p8LbhGmE">Rotterdam</a>, Netherlands. Where a convenient seaport does not exist, inland transport may be achieved with the use of <a href="/facts/Barge/9XrPkXV4">barges</a>. Lighter fuel oils can also be transported through <a href="/facts/Pipeline_transport/gEmKcFhD">pipelines</a>. The major physical supply chains of Europe are along the <a href="/facts/Rhine_River/MgJ88oaz">Rhine River</a>.

<h2 id="environmental-issues">Environmental issues</h2>
Further information: <a href="/facts/Environmental_impact_of_shipping/RSMxztxe">Environmental impact of shipping</a>
Emissions from bunker fuel burning in ships contribute to climate change and to <a href="/facts/Air_pollution/zmk9Dy7S">air pollution</a> levels in many port cities, especially where the emissions from industry and <a href="/facts/Road_traffic/cHx4tMo1">road traffic</a> have been controlled. The switch of auxiliary engines from heavy fuel oil to diesel oil at berth can result in large emission reductions, especially for <a href="/facts/Sulfur_dioxide/jDK1fIDs">SO2</a> and <a href="/facts/Particulates/RleGr5E6">PM</a>. <a href="/facts/Carbon_dioxide/xGzpppEp">CO2</a> emissions from bunker fuels sold are not added to national GHG emissions. For small countries with large international ports, there is an important difference between the emissions in territorial waters and the total emissions of the fuel sold.<a class="footnote-ref" id="fnref:39" href="#fn:39">39</a> At the 1997 <a href="/facts/United_Nations_Climate_Change_conference/mVHYuDtH">Third Conference of the Parties</a> in Kyoto, Japan, countries agreed to exempt bunker fuels, and multilateral military operations, from national emissions totals after insistence from the U.S. climate change delegation for such exemptions.<a class="footnote-ref" id="fnref:40" href="#fn:40">40</a>

<h2 id="see-also">See also</h2>

<ul><li><a href="/facts/Coconut_oil/mULGkRTS">Coconut oil</a> – Edible oil derived from coconut: an important fuel for ships in regions such as the Philippines, Papua New Guinea, and Vanuatu<a class="footnote-ref" id="fnref:41" href="#fn:41">41</a></li>
<li><a href="/facts/Diesel_fuel/lm71xc19">Diesel fuel</a> – Liquid fuel used in diesel engines</li>
<li><a href="/facts/Fuel-management_systems/sQwKfxFk">Fuel-management systems</a> – including hardware and softwarePages displaying wikidata descriptions as a fallback</li>
<li><a href="/facts/Fuel_price_risk_management/YzbsUjJN">Fuel price risk management</a></li>
<li><a href="/facts/Gas_oil_separation_plant/tAMl0jqU">Gas oil separation plant</a></li>
<li><a href="/facts/Gasoline/lcnxq5BS">Gasoline</a> – Liquid fuel derived from petroleum</li>
<li><a href="/facts/Heating_oil/gMSISJzS">Heating oil</a> – Liquid petroleum product used as a fuel oil for furnaces or boilers</li>
<li><a href="/facts/Hot-bulb_engine/BYyz15Wp">Hot-bulb engine</a> – Internal combustion engine</li>
<li><a href="/facts/Jet_fuel/4CDswF3t">Jet fuel</a> – Type of aviation fuel</li>
<li><a href="/facts/Kerosene/DoHPYXKp">Kerosene</a> – Combustible hydrocarbon liquid</li>
<li><a href="/facts/Lubricant/9PXISDwU">Lubricant</a> – Substance introduced to reduce friction between surfaces in mutual contact</li>
<li><a href="/facts/Marine_fuel_management/b7ucgsV4">Marine fuel management</a> – techniques for efficient use of fuel by shipsPages displaying wikidata descriptions as a fallback</li>
<li><a href="/facts/Petroleum_naphtha/36acq3lI">Petroleum naphtha</a> – Petroleum product</li>
<li><a href="/facts/OW_Bunker/e2PLh1uM">OW Bunker test case</a></li>
<li><a href="/facts/Pyrolysis_oil/JqQnKf70">Pyrolysis oil</a> – Petroleum substitute</li></ul>

<h2 id="external-links">External links</h2>
<ul><li><a href="http://www.nature.nps.gov/hazardssafety/toxic/fueloil.pdf">National Park Service - Fuel Oil</a> <a href="https://web.archive.org/web/20070610035043/http://www.nature.nps.gov/hazardssafety/toxic/fueloil.pdf">Archived</a> 10 June 2007 at the <a href="/facts/Wayback_Machine/nmQ3a6JC">Wayback Machine</a></li>
<li><a href="https://science.howstuffworks.com/environmental/energy/oil-refining.htm">How Oil Refining Works – HowStuffWorks</a></li>
<li><a href="https://ibia.net/">International Bunker Industry Association</a></li>
<li><a href="https://response.restoration.noaa.gov/oil-and-chemical-spills/oil-spills/oil-types.html">NOAA Oil Types</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1">"Mayor Bloomberg Presents an Update to PlaNYC: a Greener, Greater New York". NYC.gov. 22 March 2010. Archived from the original on 2 February 2017. Retrieved 22 April 2011. <a href="https://www1.nyc.gov/office-of-the-mayor/news/129-10/mayor-bloomberg-presents-update-planyc-a-greener-greater-new-york#/9" target="_blank">https://www1.nyc.gov/office-of-the-mayor/news/129-10/mayor-bloomberg-presents-update-planyc-a-greener-greater-new-york#/9</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></li>
<li id="fn:2">Office of the Mayor (9 February 2016). "Mayor de Blasio and DEP Announce That All 5,300 Buildings Have Discontinued Use of Most Polluting Heating Oil, Leading to Significantly Cleaner Air". City of New York. Archived from the original on 14 September 2017. Retrieved 14 September 2017. <a href="https://www1.nyc.gov/office-of-the-mayor/news/152-16/mayor-de-blasio-dep-that-all-5-300-buildings-have-discontinued-use-most-polluting" target="_blank">https://www1.nyc.gov/office-of-the-mayor/news/152-16/mayor-de-blasio-dep-that-all-5-300-buildings-have-discontinued-use-most-polluting</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></li>
<li id="fn:3">"U.S. Energy Information Administration (EIA)". Archived from the original on 1 November 2004. Retrieved 21 August 2009. <a href="https://web.archive.org/web/20041101051713/http://eia.doe.gov/oiaf/1605/coefficients.html" target="_blank">https://web.archive.org/web/20041101051713/http://eia.doe.gov/oiaf/1605/coefficients.html</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></li>
<li id="fn:4">Sofiev, Mikhail; Winebrake, James J.; Johansson, Lasse; Carr, Edward W.; Prank, Marje; Soares, Joana; Vira, Julius; Kouznetsov, Rostislav; Jalkanen, Jukka-Pekka; Corbett, James J. (6 February 2018). "Cleaner fuels for ships provide public health benefits with climate tradeoffs". Nature Communications. 9 (1): 406. Bibcode:2018NatCo...9..406S. doi:10.1038/s41467-017-02774-9. ISSN 2041-1723. PMC 5802819. PMID 29410475. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5802819" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5802819</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></li>
<li id="fn:5">"A global snapshot of the air pollution-related health impacts of transportation sector emissions in 2010 and 2015 | International Council on Clean Transportation". theicct.org. Retrieved 30 April 2020. <a href="https://theicct.org/publications/health-impacts-transport-emissions-2010-2015" target="_blank">https://theicct.org/publications/health-impacts-transport-emissions-2010-2015</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></li>
<li id="fn:6">"A global snapshot of the air pollution-related health impacts of transportation sector emissions in 2010 and 2015 | International Council on Clean Transportation". theicct.org. Retrieved 30 April 2020. <a href="https://theicct.org/publications/health-impacts-transport-emissions-2010-2015" target="_blank">https://theicct.org/publications/health-impacts-transport-emissions-2010-2015</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></li>
<li id="fn:7">Abbasov, Faig (4 June 2019). "Luxury cruise giant emits 10 times more air pollution (SOx) than all of Europe's cars – study". T&E (European Federation for Transport and Environment). <a href="https://www.transportenvironment.org/articles/luxury-cruise-giant-emits-10-times-more-air-pollution-sox-all-europes-cars-study" target="_blank">https://www.transportenvironment.org/articles/luxury-cruise-giant-emits-10-times-more-air-pollution-sox-all-europes-cars-study</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></li>
<li id="fn:8">Kent, James A. Riegel's Handbook of Industrial Chemistry (1983) Van Nostrand Reinhold Company ISBN 0-442-20164-8 pp.492-493 <a href="/wiki/ISBN_(identifier)" target="_blank">/wiki/ISBN_(identifier)</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></li>
<li id="fn:9">Perry, Robert H., Chilton, Cecil H. and Kirkpatrick, Sidney D. Perry's Chemical Engineers' Handbook 4th edition (1963) McGraw Hill p.9-6 <a href="#fnref:9" class="footnote-back-ref">↩</a></li>
<li id="fn:10">Kent, James A. Riegel's Handbook of Industrial Chemistry (1983) Van Nostrand Reinhold Company ISBN 0-442-20164-8 pp.492-493 <a href="/wiki/ISBN_(identifier)" target="_blank">/wiki/ISBN_(identifier)</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></li>
<li id="fn:11">Perry, Robert H., Chilton, Cecil H. and Kirkpatrick, Sidney D. Perry's Chemical Engineers' Handbook 4th edition (1963) McGraw Hill p.9-6 <a href="#fnref:11" class="footnote-back-ref">↩</a></li>
<li id="fn:12">Kent, James A. Riegel's Handbook of Industrial Chemistry (1983) Van Nostrand Reinhold Company ISBN 0-442-20164-8 pp.492-493 <a href="/wiki/ISBN_(identifier)" target="_blank">/wiki/ISBN_(identifier)</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></li>
<li id="fn:13">Perry, Robert H., Chilton, Cecil H. and Kirkpatrick, Sidney D. Perry's Chemical Engineers' Handbook 4th edition (1963) McGraw Hill p.9-6 <a href="#fnref:13" class="footnote-back-ref">↩</a></li>
<li id="fn:14">Perry, Robert H., Chilton, Cecil H. and Kirkpatrick, Sidney D. Perry's Chemical Engineers' Handbook 4th edition (1963) McGraw Hill p.9-6 <a href="#fnref:14" class="footnote-back-ref">↩</a></li>
<li id="fn:15">Kent, James A. Riegel's Handbook of Industrial Chemistry (1983) Van Nostrand Reinhold Company ISBN 0-442-20164-8 pp.492-493 <a href="/wiki/ISBN_(identifier)" target="_blank">/wiki/ISBN_(identifier)</a> <a href="#fnref:15" class="footnote-back-ref">↩</a></li>
<li id="fn:16">Perry, Robert H., Chilton, Cecil H. and Kirkpatrick, Sidney D. Perry's Chemical Engineers' Handbook 4th edition (1963) McGraw Hill p.9-6 <a href="#fnref:16" class="footnote-back-ref">↩</a></li>
<li id="fn:17">Kent, James A. Riegel's Handbook of Industrial Chemistry (1983) Van Nostrand Reinhold Company ISBN 0-442-20164-8 pp.492-493 <a href="/wiki/ISBN_(identifier)" target="_blank">/wiki/ISBN_(identifier)</a> <a href="#fnref:17" class="footnote-back-ref">↩</a></li>
<li id="fn:18">Perry, Robert H., Chilton, Cecil H. and Kirkpatrick, Sidney D. Perry's Chemical Engineers' Handbook 4th edition (1963) McGraw Hill p.9-6 <a href="#fnref:18" class="footnote-back-ref">↩</a></li>
<li id="fn:19">Perry, Robert H., Chilton, Cecil H. and Kirkpatrick, Sidney D. Perry's Chemical Engineers' Handbook 4th edition (1963) McGraw Hill p.9-6 <a href="#fnref:19" class="footnote-back-ref">↩</a></li>
<li id="fn:20">"Bunkerworld Account - Login". www.bunkerworld.com. Archived from the original on 3 March 2009. Retrieved 18 February 2009. <a href="http://www.bunkerworld.com/markets/prices/nl/rtm/" target="_blank">http://www.bunkerworld.com/markets/prices/nl/rtm/</a> <a href="#fnref:20" class="footnote-back-ref">↩</a></li>
<li id="fn:21">https://www.iso.org/standard/64247.html Archived 1 December 2017 at the Wayback Machine ISO8217:2017 <a href="https://www.iso.org/standard/64247.html" target="_blank">https://www.iso.org/standard/64247.html</a> <a href="#fnref:21" class="footnote-back-ref">↩</a></li>
<li id="fn:22">"IMO 2020 – cutting sulphur oxide emissions". www.imo.org. Retrieved 3 August 2022. <a href="https://www.imo.org/en/MediaCentre/HotTopics/Pages/Sulphur-2020.aspx" target="_blank">https://www.imo.org/en/MediaCentre/HotTopics/Pages/Sulphur-2020.aspx</a> <a href="#fnref:22" class="footnote-back-ref">↩</a></li>
<li id="fn:23">Tolson, Adrian (25 March 2021). "Welcome to the 229 Million Metric Ton Global Bunker Market!". Ship & Bunker. Archived from the original on 24 July 2021. <a href="https://shipandbunker.com/news/world/375323-welcome-to-the-229-million-metric-ton-global-bunker-market" target="_blank">https://shipandbunker.com/news/world/375323-welcome-to-the-229-million-metric-ton-global-bunker-market</a> <a href="#fnref:23" class="footnote-back-ref">↩</a></li>
<li id="fn:24">"RMG and RMK" (PDF). Archived from the original (PDF) on 26 January 2012. <a href="https://web.archive.org/web/20120126135721/http://www.chevronmarineproducts.com/docs/Requirements_for_Residual_Fuel_2010.pdf" target="_blank">https://web.archive.org/web/20120126135721/http://www.chevronmarineproducts.com/docs/Requirements_for_Residual_Fuel_2010.pdf</a> <a href="#fnref:24" class="footnote-back-ref">↩</a></li>
<li id="fn:25">"Sulfur oxides (SOx) – Regulation 14". International Maritime Organization. Archived from the original on 23 December 2014. Retrieved 11 July 2013. SOx and particulate matter emission controls apply to all fuel oil <a href="http://arquivo.pt/wayback/20141223211746/http://www.imo.org/OurWork/Environment/PollutionPrevention/AirPollution/Pages/Sulphur-oxides-%28SOx%29-%e2%80%93-Regulation-14.aspx" target="_blank">http://arquivo.pt/wayback/20141223211746/http://www.imo.org/OurWork/Environment/PollutionPrevention/AirPollution/Pages/Sulphur-oxides-%28SOx%29-%e2%80%93-Regulation-14.aspx</a> <a href="#fnref:25" class="footnote-back-ref">↩</a></li>
<li id="fn:26">Robert Wall (10 July 2013). "Rolls-Royce Revives Age of Sail to Beat Fuel-Cost Surge: Freight". Bloomberg. Archived from the original on 15 July 2013. Retrieved 11 July 2013. a development which will prompt a switch to "a much more diverse fuel pallet" <a href="https://www.bloomberg.com/news/2013-07-10/rolls-royce-revives-age-of-sail-to-beat-fuel-cost-surge-freight.html" target="_blank">https://www.bloomberg.com/news/2013-07-10/rolls-royce-revives-age-of-sail-to-beat-fuel-cost-surge-freight.html</a> <a href="#fnref:26" class="footnote-back-ref">↩</a></li>
<li id="fn:27">"DMA and DMB" (PDF). Archived from the original (PDF) on 26 January 2012. <a href="https://web.archive.org/web/20120126122253/http://www.chevronmarineproducts.com/docs/Requirements_for_Distillate_Fuel_2010.pdf" target="_blank">https://web.archive.org/web/20120126122253/http://www.chevronmarineproducts.com/docs/Requirements_for_Distillate_Fuel_2010.pdf</a> <a href="#fnref:27" class="footnote-back-ref">↩</a></li>
<li id="fn:28">Schrooten, L; De Vlieger, Ina; Int Panis, Luc; Chiffi, Cosimo; Pastori, Enrico (2009). "Emissions of maritime transport: a reference system". Science of the Total Environment. 408 (2): 318–323. Bibcode:2009ScTEn.408..318S. doi:10.1016/j.scitotenv.2009.07.037. PMID 19840885. S2CID 8271813. <a href="/wiki/Bibcode_(identifier)" target="_blank">/wiki/Bibcode_(identifier)</a> <a href="#fnref:28" class="footnote-back-ref">↩</a></li>
<li id="fn:29">Schrooten, L; De Vlieger, Ina; Int Panis, Luc; Styns, R. Torfs, K; Torfs, R (2008). "Inventory and forecasting of maritime emissions in the Belgian sea territory, an activity based emission model". Atmospheric Environment. 42 (4): 667–676. Bibcode:2008AtmEn..42..667S. doi:10.1016/j.atmosenv.2007.09.071. S2CID 93958844. <a href="/wiki/Bibcode_(identifier)" target="_blank">/wiki/Bibcode_(identifier)</a> <a href="#fnref:29" class="footnote-back-ref">↩</a></li>
<li id="fn:30">Vidal, John (21 May 2016). "The world's largest cruise ship and its supersized pollution problem". the Guardian. Archived from the original on 9 February 2019. Retrieved 21 August 2018. Cruise companies create a picture of being a bright, clean and environmentally friendly tourism sector. But the opposite is true. One cruise ship emits as many air pollutants as five million cars going the same distance because these ships use heavy fuel that on land would have to be disposed of as hazardous waste."... "Heavy fuel oil can contain 3,500 times more sulfur than diesel that is used for land traffic vehicles. Ships do not have exhaust abatement technologies like particulate filters that are standard on passenger cars and lorries <a href="https://www.theguardian.com/environment/2016/may/21/the-worlds-largest-cruise-ship-and-its-supersized-pollution-problem" target="_blank">https://www.theguardian.com/environment/2016/may/21/the-worlds-largest-cruise-ship-and-its-supersized-pollution-problem</a> <a href="#fnref:30" class="footnote-back-ref">↩</a></li>
<li id="fn:31">"bunker fuel". Cruise Law News. 31 March 2017. Archived from the original on 21 August 2018. Retrieved 21 August 2018. <a href="https://www.cruiselawnews.com/tags/bunker-fuel/" target="_blank">https://www.cruiselawnews.com/tags/bunker-fuel/</a> <a href="#fnref:31" class="footnote-back-ref">↩</a></li>
<li id="fn:32">"Clean up the Shipping Industry". Stand.earth. 14 December 2016. Archived from the original on 21 August 2018. Retrieved 21 August 2018. <a href="https://web.archive.org/web/20180821223138/https://www.stand.earth/campaigns/clean-shipping-industry" target="_blank">https://web.archive.org/web/20180821223138/https://www.stand.earth/campaigns/clean-shipping-industry</a> <a href="#fnref:32" class="footnote-back-ref">↩</a></li>
<li id="fn:33">"Bunkering". Maritime and Port Authority of Singapore (MPA). Archived from the original on 7 January 2015. Retrieved 16 January 2015. <a href="https://web.archive.org/web/20150107064443/http://www.mpa.gov.sg/sites/port_and_shipping/port/bunkering/bunkering.page" target="_blank">https://web.archive.org/web/20150107064443/http://www.mpa.gov.sg/sites/port_and_shipping/port/bunkering/bunkering.page</a> <a href="#fnref:33" class="footnote-back-ref">↩</a></li>
<li id="fn:34">MOHIT (19 October 2010). "Bunkering is Dangerous: Procedure for Bunkering Operation on a Ship". Marine Insight. Archived from the original on 31 December 2015. Retrieved 16 January 2015. Site seems to require enabling of cookies.{{cite web}}: CS1 maint: postscript (link) <a href="https://www.marineinsight.com/guidelines/bunkering-is-dangerous-procedure-for-bunkering-operation-on-a-ship/" target="_blank">https://www.marineinsight.com/guidelines/bunkering-is-dangerous-procedure-for-bunkering-operation-on-a-ship/</a> <a href="#fnref:34" class="footnote-back-ref">↩</a></li>
<li id="fn:35">Jon Gambrell and Associated Press (20 July 2013). "Oil bunkering threatens Nigeria's economy, environment". The Washington Post. Archived from the original on 9 March 2016. Retrieved 16 January 2015. <a href="https://www.washingtonpost.com/national/oil-bunkering-threatens-nigerias-economy-environment/2013/07/18/e38cb4a0-e273-11e2-aef3-339619eab080_story.html" target="_blank">https://www.washingtonpost.com/national/oil-bunkering-threatens-nigerias-economy-environment/2013/07/18/e38cb4a0-e273-11e2-aef3-339619eab080_story.html</a> <a href="#fnref:35" class="footnote-back-ref">↩</a></li>
<li id="fn:36">"Regulations for the prevention of air pollution from ships" (PDF). www.dan-bunkering.com. Retrieved 4 October 2020. <a href="https://dan-bunkering.com/Admin/Public/DWSDownload.aspx?File=%2fFiles%2fFiler%2fDB%2fPdf%2fEmission_control_Regulations.pdf" target="_blank">https://dan-bunkering.com/Admin/Public/DWSDownload.aspx?File=%2fFiles%2fFiler%2fDB%2fPdf%2fEmission_control_Regulations.pdf</a> <a href="#fnref:36" class="footnote-back-ref">↩</a></li>
<li id="fn:37">Chu Van, Thuy; Ramirez, Jerome; Rainey, Thomas; Ristovski, Zoran; Brown, Richard J. (1 May 2019). "Global impacts of recent IMO regulations on marine fuel oil refining processes and ship emissions" (PDF). Transportation Research Part D: Transport and Environment. 70: 123–134. Bibcode:2019TRPD...70..123C. doi:10.1016/j.trd.2019.04.001. ISSN 1361-9209. S2CID 133571823. <a href="https://eprints.qut.edu.au/128190/2/128190.pdf" target="_blank">https://eprints.qut.edu.au/128190/2/128190.pdf</a> <a href="#fnref:37" class="footnote-back-ref">↩</a></li>
<li id="fn:38">"Power sector's thirst for fuel oil after IMO low sulfur cap shifts bunker demand - Hellenic Shipping News Worldwide". www.hellenicshippingnews.com. Archived from the original on 16 May 2018. Retrieved 16 May 2018. <a href="https://web.archive.org/web/20180516175327/https://www.hellenicshippingnews.com/power-sectors-thirst-for-fuel-oil-after-imo-low-sulfur-cap-shifts-bunker-demand/" target="_blank">https://web.archive.org/web/20180516175327/https://www.hellenicshippingnews.com/power-sectors-thirst-for-fuel-oil-after-imo-low-sulfur-cap-shifts-bunker-demand/</a> <a href="#fnref:38" class="footnote-back-ref">↩</a></li>
<li id="fn:39">Schrooten, L; De Vlieger, Ina; Int Panis, Luc; Styns, R. Torfs, K; Torfs, R (2008). "Inventory and forecasting of maritime emissions in the Belgian sea territory, an activity based emission model". Atmospheric Environment. 42 (4): 667–676. Bibcode:2008AtmEn..42..667S. doi:10.1016/j.atmosenv.2007.09.071. S2CID 93958844. <a href="/wiki/Bibcode_(identifier)" target="_blank">/wiki/Bibcode_(identifier)</a> <a href="#fnref:39" class="footnote-back-ref">↩</a></li>
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<li id="fn:41">National Geographic magazine, April 2012 <a href="#fnref:41" class="footnote-back-ref">↩</a></li>
</ol>

Fuel oil open-in-new

Fuel oil