Heating oil is any
petroleum product
Petroleum products are materials derived from crude oil (petroleum) as it is processed in oil refineries. Unlike petrochemicals, which are a collection of well-defined usually pure organic compounds, petroleum products are complex mixtures. Mos ...
or other oil used for heating; it is a
fuel oil
Fuel oil is any of various fractions obtained from the distillation of petroleum (crude oil). Such oils include distillates (the lighter fractions) and residues (the heavier fractions). Fuel oils include heavy fuel oil (bunker fuel), marine f ...
. Most commonly, it refers to low
viscosity
Viscosity is a measure of a fluid's rate-dependent drag (physics), resistance to a change in shape or to movement of its neighboring portions relative to one another. For liquids, it corresponds to the informal concept of ''thickness''; for e ...
grades of fuel oil used for
furnaces or
boiler
A boiler is a closed vessel in which fluid (generally water) is heated. The fluid does not necessarily boil. The heated or vaporized fluid exits the boiler for use in various processes or heating applications, including water heating, centra ...
s for home heating and in other buildings. Home heating oil is often abbreviated as HHO.
Most heating oil products are chemically very similar to
diesel fuel
Diesel fuel, also called diesel oil, heavy oil (historically) or simply diesel, is any liquid fuel specifically designed for use in a diesel engine, a type of internal combustion engine in which fuel ignition takes place without a spark as a re ...
used as
motor fuel; motor fuel is typically subject to higher
fuel taxes. Many countries add
fuel dyes to heating oil, allowing law enforcement to check if a driver is
evading fuel taxes. Since 2002,
Solvent Yellow 124 has been added as a "Euromarker" in the
European Union
The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...
; untaxed diesel is known as "red diesel" in the United Kingdom.
Heating oil is commonly delivered by
tank truck
A tank truck, gas truck, fuel truck, or tanker truck (American English) or tanker (British English) is a motor vehicle designed to carry liquids or gases on roads. The largest such vehicles are similar to railroad tank cars, which are also desi ...
to residential, commercial, and
municipal buildings and stored in above-ground storage tanks ("ASTs") located in the basements, garages, or outside adjacent to the building. It is sometimes stored in
underground storage tanks (or "USTs") but less often than ASTs. ASTs are used for smaller installations due to the lower cost factor. Heating oil is less commonly used as an industrial fuel or for power generation.
Leaks from tanks and piping are an
environmental concern. In the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
, various federal and state regulations are in place regarding the proper transportation, storage and burning of heating oil, which is classified as a
hazardous material
Dangerous goods are substances that are a risk to health, safety, property or the Natural environment, environment during transport. Certain dangerous goods that pose risks even when not being transported are known as hazardous materials (syll ...
(HazMat) by federal regulators.
Technical characteristics
Heating oil consists of a mixture of
petroleum
Petroleum, also known as crude oil or simply oil, is a naturally occurring, yellowish-black liquid chemical mixture found in geological formations, consisting mainly of hydrocarbons. The term ''petroleum'' refers both to naturally occurring un ...
-derived
hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and Hydrophobe, hydrophobic; their odor is usually fain ...
s in the 14- to 20-carbon atom range that condense between during
oil refining
An oil refinery or petroleum refinery is an industrial processes, industrial process Factory, plant where petroleum (crude oil) is transformed and refining, refined into products such as gasoline (petrol), diesel fuel, Bitumen, asphalt base, ...
. Heating oil condenses at a lower temperature than
petroleum jelly
Petroleum jelly, petrolatum (), white petrolatum, soft paraffin, or multi-hydrocarbon, CAS number 8009-03-8, is a semi-solid mixture of hydrocarbons (with carbon numbers mainly higher than 25), originally promoted as a topical ointment for i ...
,
bitumen
Bitumen ( , ) is an immensely viscosity, viscous constituent of petroleum. Depending on its exact composition, it can be a sticky, black liquid or an apparently solid mass that behaves as a liquid over very large time scales. In American Engl ...
,
candle wax, and
lubricating oil, but at a higher temperature than
kerosene
Kerosene, or paraffin, is a combustibility, combustible hydrocarbon liquid which is derived from petroleum. It is widely used as a fuel in Aviation fuel, aviation as well as households. Its name derives from the Greek (''kērós'') meaning " ...
, which condenses between . The heavy (C20+) hydrocarbons condense between .
Heating oil produces to and weighs 8.2 pounds per US gallon (0.95 kg/L).
Number 2 fuel oil has a
flash point
The flash point of a material is the "lowest liquid temperature at which, under certain standardized conditions, a liquid gives off vapours in a quantity such as to be capable of forming an ignitable vapour/air mixture".
The flash point is somet ...
of .
Historically, the legal difference between diesel and heating oil in the United States has been sulfur allowance. Diesel for machinery and equipment must be below 15 ppm sulfur content while heating oil needed only stay below 500 ppm sulfur. However, most heating oil in the United States is now "ultra-low sulfur heating oil" (ULSHO) and meets the same 15 ppm standard.
United States and Canada

Heating oil is known in the United States as No. 2 heating oil. In the U.S., it must conform to
ASTM
ASTM International, formerly known as American Society for Testing and Materials, is a standards organization that develops and publishes voluntary consensus technical international standards for a wide range of materials, products, systems and s ...
standard D396.
Diesel and
kerosene
Kerosene, or paraffin, is a combustibility, combustible hydrocarbon liquid which is derived from petroleum. It is widely used as a fuel in Aviation fuel, aviation as well as households. Its name derives from the Greek (''kērós'') meaning " ...
, while often confused as being similar or identical, must each conform to their respective ASTM standards. Heating oil is widely used in both the United States and Canada, with U.S. residential use most common in the northeastern states of
New York and
Pennsylvania
Pennsylvania, officially the Commonwealth of Pennsylvania, is a U.S. state, state spanning the Mid-Atlantic (United States), Mid-Atlantic, Northeastern United States, Northeastern, Appalachian, and Great Lakes region, Great Lakes regions o ...
and in
New England
New England is a region consisting of six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York (state), New York to the west and by the ...
, collectively accounting for 85% of total U.S. residential heating oil use. In the United States,
biodiesel
Biodiesel is a renewable biofuel, a form of diesel fuel, derived from biological sources like vegetable oils, animal fats, or recycled greases, and consisting of long-chain fatty acid esters. It is typically made from fats.
The roots of bi ...
blends of B5 (5% biodiesel) and B20 (20% biodiesel) are available in most markets as a lower and cleaner burning heating fuel.
The heating oil
futures contract
In finance, a futures contract (sometimes called futures) is a standardized legal contract to buy or sell something at a predetermined price for delivery at a specified time in the future, between parties not yet known to each other. The item tr ...
trades in units of with a minimum fluctuation of $0.0001 per gallon and (for the USA) is based on delivery in
New York Harbor.
The Department of Energy tracks the prices homeowners pay for home heating fuel (oil and propane). There are also a number of websites that allow home owners to compare the price per gallon they are paying with the Department of Energy data as well as other consumers in their area. Likewise th
US Energy Information Administrationcollects heating
oil price
The price of oil, or the oil price, generally refers to the spot price of a Oil barrel, barrel () of benchmark crude oil—a reference price for buyers and sellers of crude oil such as West Texas Intermediate (WTI), Brent Crude, Dubai Crud ...
statistics and maintains historical price data for all major US markets during each heating season. The US Department of Energy also supports research and development for heating oil technology through th
National Oilheat Research Alliance Additional information about biodiesel heating oil use can also be found at th
National Biodiesel Board's site
Heating oil is mostly used in the northeastern and northwestern urban United States and a strong market presence in rural areas as well. Most of the northeast's heating oil comes from Irving Oil's refinery in
Saint John, New Brunswick
Saint John () is a port#seaport, seaport city located on the Bay of Fundy in the province of New Brunswick, Canada. It is Canada's oldest Municipal corporation, incorporated city, established by royal charter on May 18, 1785, during the reign ...
, the largest oil refinery in Canada.
Republic of Ireland and Northern Ireland
Heating oil is the most common fuel for home heating in Northern Ireland due to the late development of a
natural gas
Natural gas (also fossil gas, methane gas, and gas) is a naturally occurring compound of gaseous hydrocarbons, primarily methane (95%), small amounts of higher alkanes, and traces of carbon dioxide and nitrogen, hydrogen sulfide and helium ...
network. Common suppliers of heating oil in Ireland are
Maxol,
Patterson Oil and
Emo Oil.
England, Scotland and Wales
In England, Scotland and Wales, there are two types of heating oil: commercial heating oil – referring to gas oil, i.e.
red diesel – and domestic heating oil – meaning
kerosene
Kerosene, or paraffin, is a combustibility, combustible hydrocarbon liquid which is derived from petroleum. It is widely used as a fuel in Aviation fuel, aviation as well as households. Its name derives from the Greek (''kērós'') meaning " ...
, specificall
BS 2869 Class C2 kerosene Heating oil is used for home heating in England, Scotland and Wales, typically in premises away from mains gas. There are around 1.5 million people in Great Britain using oil for home heating.
Great Britain has many suppliers of heating oil ranging from large companies such as
Crown Oil to local and independent heating oil suppliers such as
J. R. Rix & Sons. Many villages may use
buying groups to order heating oil at the same time, thereby accessing lower costs. Many heating oil suppliers will choose to list their prices on independent heating oil price comparison websites. These sites draw in home heating oil users and compare various local supplier prices in order to provide the lowest price available. In the UK it is possible to search for prices by town name, county and postcode prefix.
The Department of Energy and Climate Change (DECC) have referred the UK oil market to the Office of Fair Trading (OFT) for review. The OFT has resolved to look at the structure of the market, with a view of the fairness for consumers and alternative energy options for off-grid consumers such as
heat pumps
A heat pump is a device that uses electricity to transfer heat from a colder place to a warmer place. Specifically, the heat pump transfers thermal energy using a heat pump and refrigeration cycle, cooling the cool space and warming the warm s ...
.
Heating oil storage regulations in the United Kingdom

Heating oil storage in the United Kingdom is governed by regulations that ensure the safe installation and usage of oil storage tanks. It is a criminal offence to keep a tank that violates these regulations, and the owners are liable for fines, penalties and any costs incurred as a result of cleaning up oil spills.
The regulations are designed to minimise the risk of damaging pollution and reduce the likelihood of oil being stored in hazardous environments, such as a building without proper fire safety measures. The regulations that govern oil storage tanks ar
The Control of Pollution (Oil Storage) England Regulations (2001)The Pollution Prevention Guidelines (PPG 2)and
The Building Regulations (Approved Document J).
The Oil Storage Regulations (2001) apply to oil tanks used for commercial and industrial purposes, or domestic tanks over 3500 litres in capacity. They state that the storage tank should be of "sufficient strength and structural integrity to ensure that it is unlikely to burst or leak in its ordinary use". The tank, along with any filters, gauges, valves or ancillary equipment, must be contained within a secondary unit or bund that has at least 110% of the capacity of the inner tank. If the tank has a fill pipe that is not contained within the secondary unit, a drip tray must be installed. They also require the use of an automatic overfill prevention if it is not "reasonably practical" to monitor the oil levels within the tank.
The Building Regulations
Approved Document J covers the legal requirements for the installation of the tanks within the premises of a building. The regulations state that any new tank larger than 2,500 litres must be stored within a
bunded tank or secondary containment that is a minimum of 110% of the tank's capacity. If a tank is single skinned and smaller than 2,500 litres, it must be given an individual site pollution risk assessment. This highlights any pollution or hazard risks such as the possibility of the oil escaping and reaching a river or stream, or the risk of a collision if the storage tank is located near a road.
They further state that all tanks must be installed on a surface strong enough to support a full storage tank. The surface must be flat, even and fire-resistant, and should extend at least 300mm beyond the boundaries of the tank. A paving stone surface must be at least 42mm thick, and a concrete surface must be at least 100mm thick. The document also states that the tank should be situated at least 1800mm away from any potential hazards, such as doors, windows, appliance flue terminals, non-fire rated buildings such as garden fences, and at least 760mm from non-fire rated smaller structures such as wooden fences.
A safe, secure tank that complies with all regulations will look similar to the diagram above. It details the different parts of the tank that need to be checked in order to ensure the tank is legal, including where the ancillary equipment should be located and the presence of an automatic overfill prevention.
See also
*
Central oil storage
*
Oil burner
*
Fuel price risk management Fuel price risk management, a specialization of both financial risk management and oil price analysis and similar to conventional risk management practice, is a continual cyclic process that includes risk assessment, risk decision making and the imp ...
*
Hazardous material
Dangerous goods are substances that are a risk to health, safety, property or the Natural environment, environment during transport. Certain dangerous goods that pose risks even when not being transported are known as hazardous materials (syll ...
*
Heating, ventilation and air-conditioning (HVAC)
*United States:
**
New England Fuel Institute
**
Northeast Home Heating Oil Reserve
Footnotes
{{DEFAULTSORT:Heating Oil
Oils
Petroleum products
Residential heating