A filling station, also known as a fueling station, garage, gasbar (Canada), gas station (U.S. and Canada), petrol bunk (India), petrol pump (India), petrol garage, petrol kiosk (Singapore), petrol station (United Kingdom and Hong Kong) "'servo"' in Australia or service station, is a facility which sells fuel and lubricants for motor vehicles. The most common fuels sold today are petrol (known also as gasoline or gas in the U.S. and Canada, while "petrol" is also known in Canada), diesel fuel and electric energy. Filling stations that only sell electric energy are also known as charging stations.
Fuel dispensers are used to pump petrol/gasoline, diesel, CNG, CGH2, HCNG, LPG, LH2, ethanol fuel, biofuels like biodiesel, kerosene, or other types of fuel into vehicles and calculate the financial cost of the fuel transferred to the vehicle. Fuel dispensers are also known as bowsers (in some parts of Australia),[1] petrol pumps (in most Commonwealth countries) or gas pumps (in North America).
Many filling stations also combine small convenience stores, and some also sell propane or butane and have added shops to their primary business. Conversely, some chain stores, such as supermarkets, discount superstores, warehouse clubs, or traditional convenience stores, have provided filling stations on the premises.
The term "gas station" is mostly used in the US and in Canada, where the fuel is known as "gasoline" or "gas" as in "gas pump". In some regions of Canada, the term "gas bar" is used. Elsewhere in the English-speaking world, mainly in the Commonwealth, the fuel is known as "petrol", and the term "petrol station" or "petrol pump" is used. In the United Kingdom and South Africa "garage" is still commonly used, even though the petrol station may have no service/maintenance facilities which would justify this description. Similarly, in Australia, the term "service station" ("servo") describes any petrol station. In Japanese English, it is called a "gasoline stand". In Indian English, it is called a petrol pump or a petrol bunk. In some regions of America and Australia, many filling stations have a mechanic on duty, but this is uncommon in other parts of the world.
The first places that sold gasoline/petrol were pharmacies, as a side business. The first gas/petrol station was the city pharmacy in Wiesloch, Germany, where Bertha Benz refilled the tank of the first automobile on its maiden trip from Mannheim to Pforzheim and back in 1888. Since 2008 the Bertha Benz Memorial Route commemorates this event.[7][8]
The increase in automobile ownership after Henry Ford started to sell automobiles that the middle class could afford resulted in a greater demand for filling stations. The world's first purpose built gas station was constructed in St. Louis, Missouri in 1905 at 420 S. Theresa Avenue. The second gas station was constructed in 1907 by Standard Oil of California (now Chevron) in Seattle, Washington at what is now Pier 32. Reighard's gas station in Altoona, Pennsylvania claims that it dates from 1909 and is the oldest existing gas station in the United States. Early on, they were known to motorists as "filling stations". The first "drive-in" filling station, Gulf Refining Company opened to the motoring public in Pittsburgh in 1913.[9] Prior to this, automobile drivers pulled into almost any general or hardware store, or even blacksmith shops in order to fill up their tanks. On its first day, the station sold 30 gallons of gasoline at 27 cents per gallon. This was also the first architect-designed station and the first to distribute free road maps.[10]
Most filling stations are built in a similar manner, with most of the fueling installation underground, pump machines in the forecourt and a point of service inside a building. Single or multiple fuel tanks are usually deployed underground. Local regulations and environmental concerns may require a different method, with some stations storing their fuel in container tanks, entrenched surface tanks or unprotected fuel tanks deployed on the surface. Fuel is usually offloaded from a tanker truck into the tanks through a separate valve, located on the filling station's perimeter. Fuel from the tanks travels to the dispenser pumps through underground pipes. For every fuel tank, direct access must be available at all times. Most tanks can be accessed through a service canal directly from the forecourt.
Older stations tend to use a separate pipe for every kind of available fuel and for every dispenser. Newer stations may employ a single pipe for every dispenser. This pipe houses a number of smaller pipes for the individual fuel types. Fuel tanks, dispenser and nozzles used to fill car tanks employ vapor recovery systems, which prevents releases of vapor into the atmosphere with a system of pipes. The exhausts are placed as high as possible. A vapor recovery system may be employed at the exhaust pipe. This system collects the vapors, liquifies them and releases them back into the lowest grade fuel tank available.
The forecourt is the part of a filling station where vehicles are refueled. Fuel dispensers are placed on concrete plinths, as a precautionary measure. Additional elements may be employed, including metal barriers. The area around the fuel dispensers must have a drainage system. Since fuel sometimes spills on the ground, as little of it as possible should penetrate the soil. Any liquids present on the forecourt will flow into a channel drain before it enters a petrol interceptor which is designed to capture any hydrocarbon pollutants and filter these from rainwater which may then proceed to a foul sewer, stormwater drain or to ground.
If a filling station allows customers to pay at the register, the data from the dispensers may be transmitted via RS232 or Ethernet to the point of sale, usually inside the filling station's building, and fed into the station's cash register operating system. The cash register system gives a limited control over the fuel dispenser, and is usually limited to allowing the clerks to turn the pumps on and off. A separate system is used to monitor the fuel tank's status and quantities of fuel. With sensors directly in the fuel tank, the data is fed to a terminal in the back room, where it can be downloaded or printed out. Sometimes this method is bypassed, with the fuel tank data transmitted directly into an external database.
Some filling stations include tire air pump and automatic car wash facilities with vacuum cleaners.
The underground modular filling station is a construction model for filling stations that was developed and patented by U-Cont Oy Ltd in Finland in 1993. Afterwards the same solution was developed in Florida, USA. Above-ground modular filling stations were built in the 1980s in eastern Europe and especially in Soviet Union, but for the stations' lack of fire safety they were not built in other parts of Europe. The construction model for underground modular filling station makes the installation time shorter, designing easier and the manufacturing less expensive. As a proof of the model's installation speed an unofficial world record of filling station installation was made by U-Cont Oy Ltd when a modular filling station was built in Helsinki, Finland in less than three days, including groundwork. The safety of modular filling stations has been tested in a filling station simulator, in Kuopio, Finland. These tests have included for instance burning cars and explosions in the station simulator.[11][12]
There are generally two types of filling stations in the US and Canada: premium and discount brands.
Filling stations with premium brands sell well-recognized and often international brands of gasoline, including Exxon and its Esso brand, Citgo, Hess, Chevron, Mobil, Shell, Sinclair, Sunoco (US), BP, Valero and Texaco. Non-international premium brands include Petrobras, Petro-Canada (owned by Suncor Energy Canada), and Pemex. Premium brand stations accept credit cards, often issue their own company cards (a.k.a. fuel cards) and may charge higher prices. Many of them have fully automated pay-at-the-pump facilities. Premium gas stations tend to be highly visible from highway and freeway exits, utilizing tall signs to display their brand logos.
Discount brands are often smaller, regional chains or independent stations, offering lower prices on gasoline. Most purchase wholesale gasoline from independent suppliers or from the major petroleum companies. Lower-priced gas stations are also found at some supermarkets (Albertsons, Kroger, Giant, Weis Markets, Safeway, Vons, Meijer, Loblaws/Real Canadian Superstore, Canadian Tire, and Giant Eagle), convenience stores (7-Eleven, Cumberland Farms, Sheetz and Wawa), discount stores (Wal-Mart) and warehouse clubs (Costco, Sam's Club, and BJ's Wholesale Club). At some stations (such as Vons, Costco, BJ's Wholesale Club, or Sam's Club), consumers are required to hold a special membership card in order to receive the discounted price, and/or pay only with either the chain's cash card or a credit card issuer exclusive to that chain. In some areas, such as New Jersey, this practice is illegal, and stations are required to sell to all. Some convenience stores, such as 7-Eleven and Circle K, have co-branded their stations with one of the premium brands.
Some countries have only one brand of petrol station. In Mexico, where the oil industry is state-owned and prices are regulated, the country's main operator of petrol stations is Pemex. In Malaysia, Shell is the dominant player by number of stations with government owned Petronas coming in second. Meanwhile in Indonesia, the dominant player by number of stations is the government-owned Pertamina, although other companies such as Total and Shell are increasingly found in big cities such as the capital Jakarta or Surabaya.[13]
Some companies, such as Shell, use their brand worldwide, however, Chevron uses its inherited brand Caltex in Asia Pacific, Australia and Africa, and its Texaco brand in Europe and Latin America. ExxonMobil uses its Exxon and Mobil brands but is still known as Esso (the forerunner company name, Standard Oil - S. O.) in many places. In Brazil, the main operator is Petrobras but Esso, Ipiranga, Texaco and Shell are also present. In the United Kingdom, the two largest are BP and Shell. All of the "Big Four" supermarket chains also operate filling stations, Morrisons, Sainsburys, Asda and Tesco, as well as some of the smaller supermarkets such as The Co-operative Group and Waitrose.
Indian Oil operates approximately 15,000 petrol stations in India.
Iceland is the only nation in the world that has filling stations dispensing hydrogen fuel for cars powered by fuel cells. It is also the only nation capable of producing hydrogen in adequate quantities, because Iceland's volcanic activity gives it plentiful geothermal energy.
In British Columbia, it is now law that customers either pre-pay for the fuel or pay at the pump. The law is called "Grant's Law"[14] and is intended to protect workers from "gas-and-dash" crimes. In other provinces pump-first-and-pay-later option is still widely available, even though some pumps may require either a prepayment or a payment at the pump at night hours.
In the Republic of Ireland, most petrol stations allow for customers to pump fuel before settling the bill. Some petrol stations have pay-at-the-pump facilities.
Most stations require the customer to pump the fuel, then pay in the shop. In some cases, often when a station has been having problems with fuel theft, they may temporarily require advance payment.
A large majority of stations will allow customers to pay with a chip and pin device in store. Many have a pay at the pump system, where customers can enter their Pin number prior to filling.
In small towns and rural areas, gas stations sometimes allow customers to pump gas first and pay afterwards. Due to the higher incidence of crime in large urban areas (especially drive-offs), or clerks too busy to deal with customers short of funds, all customers there must generally pay before pumping fuel.
Modern gas stations have pay-at-the-pump capabilities — in most cases credit, debit, ATM cards, fuel cards and fleet cards are accepted. At some stations, cash is also taken at the pump, although customers must collect their change at a cashier window which is often bullet-proof. Occasionally a station will have a pay-at-the-pump-only period per day, when attendants are not present, often at night, and some stations are pay-at-the-pump-only 24 hours a day.
Filling stations typically offer one of three types of service to their customers: full service, minimum service or self service.
In the past, filling stations in the United States offered a choice between full service and self service. Until the 1970s, full service was the norm, and self service was rare.
The first self service station in Canada was located in Winnipeg, Manitoba, in 1949 and was operated by independent Henderson Thriftway Petroleum, run by Bill Henderson.[15] The first self service gas station in the United States was in Omaha, Nebraska, in 1958, run by Sam Rosenbaum.
Today, few stations advertise full service. Full service stations are more common in wealthy and upscale areas. The cost of full service is usually assessed as a fixed amount per U.S. gallon.
All stations in New Jersey and Oregon offer only full service and mini service; attendants are required to pump gas because customers are barred by statutes in both states from pumping their own gas. New Jersey banned self-service gasoline in 1949 after lobbying by service station owners. Proponents of the ban cite safety and jobs as reasons to keep the ban.[16] Likewise, the 1951 Oregon statute banning self-service gasoline lists 17 different justifications, including the flammability of gas, the risk of crime from customers leaving their car, the toxic fumes emitted by gasoline, and the jobs created by requiring mini service.[17] In addition, the ban on self-service gasoline is seen as part of Oregonian culture. One commentator noted, “The joke is when babies are born in Oregon, the doctor slaps their bottom, ‘No self-serve and no sales tax’ [. . .] It’s as much a cultural issue as an economic issue. It’s a way of life.”[18] In 1982, Oregon voters rejected a ballot measure sponsored by the service station owners, which would have legalized self-service gas.[19]
The town of Huntington, New York bans gasoline self-service to save jobs. The ban went in effect in the early 1970s during a recession.
The constitutionality of the self-service bans has been disputed. The Oregon statute was brought into court in 1989 by ARCO, and the New Jersey statute was challenged in court in 1950 by a small independent service station, Rein Motors. Both failed. New Jersey governor Jon Corzine sought to lift the ban on self service for New Jersey. He asserted that it would be able to lower gas prices, but some New Jerseyans have argued that it can cause drawbacks, especially unemployment.
In New Jersey and Oregon, it is legal for customers to pump their own diesel (although not every station permits diesel customers to do so; truck stops typically do). In Oregon, "certain nonretail" customers may also pump their own fuel.[20]
Many gas stations also have convenience stores which sell food, beverages, cigarettes, lottery tickets, motor oil, and sometimes auto parts. Prices for these and other items tend to be higher at convenience stores than they would be at a supermarket or discount store. Sometimes, cigarettes are priced higher than normal, or they can be priced at the state minimum at stations such as Hess, Sheetz, Wawa, and Royal Farms.
In some U.S. states, beer, wine, and liquor are sold in gas stations, though this practice varies according to state law (see Alcohol laws of the United States by state). Nevada allows the sale of beer, wine, liquor, and the operation of slot and video poker machines at gas stations 24/7. Missouri also allows the sale of beer, wine, and liquor without limitation at gas stations (see Alcohol laws of Missouri).
Many gas stations also provide squeegees, towels, and toilet facilities for customer use, but discount gas stations might not provide those amenities. Many gas stations have air compressors with tire gauges and water machines. Some machines are free of charge, while others charge a small fee to use (usually around 75 cents). In many states of the U.S., state law requires that paying customers must be provided with free air compressor service. In most cases, a token provided by the attendant is used in lieu of coins. As late as the 1960s, many service stations in the U.S. provided free maps to customers.
Some gas stations are equipped with car washes. Car washes are sometimes offered free of charge or at a discounted price with a certain amount of gas purchased. Conversely, some car washes operate gas stations to supplement their businesses.
There are a number of gas stations with a fast food outlet inside, such as McDonald's, Jack in the Box, Pizza Hut, Sbarro, Subway, Dunkin Donuts, Taco Bell, or Wendy's. These are usually "express" versions with limited seating and limited menus, though some may be regular-sized and have spacious seating. These larger-sized restaurants are common at truck stops and toll road service plazas. In Canada and some areas of the United States, it is common to find a small Tim Hortons outlet inside gas stations.
In European Union (EU) member states, petrol (gas) prices are much higher than in North America due to higher fuel excise or taxation, although the base price is also higher than in the U.S. Occasionally, price rises trigger national protests. In the UK a large-scale protest in the summer of 2000, known as 'The Fuel Crisis', caused wide-scale havoc not only across the UK, but also in some other EU countries. The British government eventually backed down by indefinitely postponing a planned increase in fuel duty. This was partially reversed during December 2006 when Gordon Brown (UK Chancellor of the Exchequer) raised the fuel duty by 1.25 pence per litre.
In much of Europe, including Britain, France and Germany, filling stations operated by large supermarket and hypermarket outlets usually price fuel more competitively than stand-alone filling stations. In most of mainland Europe, sales tax is lower on diesel fuel than on petrol (gas), and diesel is accordingly the cheaper fuel: in the UK and in Switzerland, however, diesel enjoys no tax advantage and retails at a higher price than petrol.
Nearly all filling stations in North America advertise their prices on large signs outside the stations. Some locations have laws requiring such signage.[21]
In Canada and the United States, federal, state/provincial and local sales taxes are usually included in the price, although Petro Canada has started to provide a complete tax breakdown on purchase receipts and it is also posted at the pump. Gas taxes are often intended to fund transportation projects such as the maintenance of existing roads and construction of new ones. However, sometimes the funds are directed to other projects or government expenses.
In the United States, the states of California and Hawaii typically have the highest gasoline prices, while the lowest prices can be found in oil producing states like Oklahoma and Texas. In Canada, prices are typically highest in the provinces of British Columbia and Quebec, and the lowest in the oil-producing province of Alberta. The provinces of Prince Edward Island (PEI), Newfoundland and Labrador, New Brunswick, and Nova Scotia have instituted gasoline price regulation, which is intended to protect small rural gas stations from low profit margins due to low volume.
Individual gas stations in the United States have little if any control over gasoline prices. The wholesale price of gasoline is determined according to area by oil companies which supply the gasoline, and their prices are largely determined by the world markets for oil. Individual gas stations are unlikely to sell gasoline at a loss, and the margin—typically between 7 and 11 cents a U.S. gallon—that they make from gasoline sales is limited by the fact that the market is highly competitive. A gas station which charges significantly more than the wholesale price will lose customers to other gas stations. Because of this, most gas stations sell higher-margin food products inside their convenience stores.
Even with oil market fluctuations, prices for gasoline in the United States are among the lowest in the industrialized world; this is principally due to a difference in taxes. While the price of gasoline in Europe is more than twice that in the United States, the price of gas excluding taxes is nearly identical in the two areas. Some Canadians and Mexicans, close to the U.S. border, drive into the United States to purchase cheaper gasoline at gas stations in border communities.
Due to heavy fluctuations of gas price in the United States, some gas stations offered their customers the option to buy and store gas for future uses, such as the service provided by First Fuel Bank.
In order to save money, some consumers in Canada and the United States inform each other about low and high prices through the use of gasoline price websites. Such websites allow users to share prices advertised at filling stations with each other by posting them to a central server. Consumers then may check the prices listed in their geographic area in order to select the station with the lowest price available at the time. Some television and radio stations also compile pricing information via viewer/listener reports of pricing or reporter observations and present it as a regular segment of their newscasts, usually before or after traffic reports. These price observations must be done visually by reading the pricing sign outside a station, as many companies specifically prohibit their employees from publicizing their prices via a telephone inquiry from a customer due to competitive concerns. In Canada it is illegal to provide any gas pricing from a gas station via phone as per the federal government. It is criminal offence to get into arrangements with other competitors, suppliers or customers for any of the following arrangements written or verbal:
Gas stations must never hold discussions with other competitors regarding pricing policies and methods, terms of sale, costs, allocation of markets or boycotts of our petroleum products.[22]
In other energy-importing countries like Japan, gasoline/petroleum costs are higher than in the United States because of fuel transportation costs or taxes. On the other hand, some of the major oil-producing countries such as the Gulf States, Iran, Iraq, and Venezuela provide subsidized fuel at well below market prices. This practice tends to encourage heavy consumption. Hong Kong has some of the highest pump prices in the world, but most customers are given discounts as card members. Also in Western Australia a programme called Fuelwatch means that most WA filling stations have to notify their "tomorrow prices" by 2pm each day. Prices are changed at 6am each morning, and must be held for 24 hours. Each afternoon, the prices for the next day are released to the public and the media, allowing consumers to make a decision whether to fill up today or tomorrow, safe in the knowledge that prices cannot change.
In New Zealand, a filling station is often referred to as a service station, garage, or petrol station, even though the filling station may not offer mechanical repairs or assistance with dispensing fuel. Levels of service available include full service, for which assistance in dispensing fuel is offered, as well as offers to check tyre pressure or clean vehicle windscreens. This type of service is becoming uncommon in New Zealand, particularly Auckland. Further south of Auckland, many filling stations offer full service. There is also help service or assisted service, for which customers must request assistance before it is given, and self service, for which no assistance is available.
In the UK, a 'service station' refers to much larger facilities, usually attached to motorways (see rest area) or major truck routes, which provide food outlets, large parking areas, and often other services such as hotels, arcade games, and shops in addition to 24-hour fuel supplies and a higher standard of restrooms. Fuel is typically more expensive from these outlets due to their premium locations. UK service stations do not usually repair automobiles.
In the U.S., a filling station that also offers services such as oil changes and mechanical repairs to automobiles is called a service station. Until the 1970s, the vast majority of gas stations were service stations; now only a minority are. This kind of business provided the name for the U.S. comic strip Gasoline Alley, where a number of the characters worked. List of Gas stations. This arrangement occurs on many toll roads and some interstate freeways and is called an oasis, service plaza, or truck stop. In many cases, these centers might have a food court or cafeteria. In the U.S., Pilot Flying J and TravelAmerica are two of the most common full-service chains.
Often, the state government maintains public rest areas directly connected to freeways, but does not rent out space to private businesses, as this is specifically prohibited by law via the Interstate Highway Act of 1956 which created the national Interstate Highway System, except sites on freeways built before January 1, 1960, and toll highways that are self-supporting but have Interstate designation, under a grandfather clause. As a result, such areas often provide only minimal services such as restrooms and vending machines.
In turn, private entrepreneurs develop additional facilities, such as restaurants, gas stations, and motels in clusters on private land adjacent to major interchanges. Because these facilities are not directly connected to the freeway, they usually have huge signs on poles several hundred feet high. This way, travelers will be able to spot them several minutes in advance and exit accordingly. Sometimes, the state will also post small official signs (normally blue) indicating what types of gas stations, restaurants, and/or hotels are available at an upcoming exit; businesses may add their logos to these signs for a fee.
In Australia, gasoline is unleaded, and available in 91 (Normally uses up to 10% ethanol), 95, 98 and 100 octanes (names of various gasolines differ from brand to brand), fuel additives for use in cars originally designed for leaded fuel are available at most gas stations.
In Canada, the most commonly found octane grades are 87 (regular), 89 (mid grade) and 91 (premium), using the "(R+M)/2 Method".
In China, the most commonly found octane grade is RON 91 (regular), 93 (mid grade) and 97 (premium). Almost all of the fuel has been unleaded since 2000. In some premium gas stations in large cities, such as Petrol China and SinoPec, RON 98 gas is sold for racing cars.
In Europe, gasoline is unleaded and available in 95 RON (Eurosuper) and, in nearly all countries, 98 RON (Super Plus) octanes; in some countries, 91 RON octane gasoline is offered as well. In addition, 100 RON petrol is offered in some countries in continental Europe (Shell markets this as V-Power Racing [1]). Some stations offer 98 RON with lead substitute (often called "Lead-Replacement Petrol, or LRP).
In New Zealand, petrol is unleaded, and most commonly available in 91 RON ("Regular") and 95 RON ("Premium"). 98 RON is available at selected BP ("Ultimate") and Mobil ("Synergy 8000") service stations instead of the standard 95 RON. 96 RON was replaced by 95 RON, and subsequently abolished in 2006. Leaded fuel was abolished in 1996.
In the UK, the most common petrol grade (and lowest octane generally available) is 'Premium' 95 RON unleaded. 'Super' is widely available at 97 RON and some large brands offer 98 - 99 RON fuel as a premium product costing up to 10% more than standard 'premium' fuel (for example Shell V-Power, BP Ultimate or Tesco 99). Leaded fuel is not widely available. A 102-octane fuel is available in the UK at a limited number of BP stations (for a far higher price than other fuels), for racers and car enthusiasts. Although BP will be removing BP Ultimate 102 octane unleaded from its range of fuels from the end of March 2010
In the United States, all motor vehicle gasoline is unleaded and is available in several grades, which are differentiated by octane rating: 87 (Regular), 89 (Mid-Grade), and 93 (Premium) are typical grades [2]. The maximum octane rating in California is generally 91. Minimum octane levels are often lower in the Mountain States, where regular unleaded can be rated as low as 85 octane.
In the U.S. gasoline is described in terms of its "pump octane", which is the mean of their "RON" (Research Octane Number) and "MON" (Motor Octane Number). Labels on gasoline pumps in the U.S. typically describe this as the "(R+M)/2 Method". Some nations describe fuels according to the traditional RON or MON ratings, so octane ratings cannot always be compared with the equivalent U.S. rating by the "(R+M)/2 method".
In Europe and Australia, the customer selects one of several color-coded nozzles depending on the type of fuel required. The filler pipe of unleaded fuel is smaller than the one for leaded (substitute) ones. The tank filler opening has a corresponding diameter. This is to prevent filling the tank with the wrong fuel. Leaded fuel damages the catalytic converter. In some European countries, leaded fuel is no longer generally available, or LRP (lead replacement petrol) may be the only such fuel available.
In most stations in Canada and the USA, the pump often has a single nozzle and the customer selects the desired octane grade by pushing a button. Some pumps require the customer to pick up the nozzle first, then lift a lever underneath it. Others are designed so that lifting the nozzle automatically releases a switch. Some newer stations now have separate nozzles for different types of fuel. Where diesel fuel is provided, it is usually dispensed from a separate nozzle even if the various grades of gasoline share the same nozzle.
Motorists occasionally pump gasoline into a diesel car by accident. The converse is almost impossible because diesel pumps have a large nozzle with a diameter of 15⁄16 inches (23.8 mm) which does not fit the 13⁄16-inch (20.6 mm) filler, and the nozzles are protected by a lock mechanism or a lift-able flap. Diesel in a gasoline engine however — while creating large amounts of smoke — does not normally cause permanent damage if it is drained once the mistake is realized. However even a liter of gas added to the tank of a modern diesel car can cause irreversible damage to the injection pump and other components through a lack of lubrication. In some cases, the car has to be scrapped because the cost of repairs exceeds its value. The issue is not clear-cut as older diesels using completely mechanical injection can tolerate some gasoline — which has historically been used to "thin" diesel fuel in winter.
It is prohibited to use open flames and, in some places, mobile phones[23] on the forecourt of a gas station because of the risk of igniting gasoline vapor. In the U.S. the fire marshal is responsible for regulations at the gas pump. Most localities ban smoking, open flames and running engines. Since the increased occurrence of static-related fires many stations now have warnings about leaving the refueling point.
Automobiles can build up static charges by driving on dry pavements. However many tire compounds contain enough carbon black to provide an electrical ground and thus are safer. New "high mileage" tires use more silica and can increase the buildup of static. A driver who does not discharge static by contacting a conductive part of the automobile will carry it to the insulated handle of the nozzle and the static potential will eventually be discharged when this purposely grounded arrangement is put into contact with the metallic filler neck of the vehicle. Ordinarily, vapor concentrations in the area of this filling operation are below the lower explosive limit (LEL) of the product being dispensed, so the static discharge causes no problem. The problem with ungrounded gas cans results from a combination of vehicular static charge, the potential between the container and the vehicle, and the loose fit between the grounded nozzle and the gas can. This last condition causes a rich vapor concentration in the ullage (the unfilled volume) of the gas can, and a discharge from the can to the grounded hanging hardware (the nozzle, hose, swivels and break-a-ways) can thus occur at a most inopportune point. The Petroleum Equipment Institute has recorded incidents of static-related ignition at refueling sites since early 2000. [3]
Although urban legends persist that a mobile phone can cause sparks or a build-up of static electricity in the user, this has not been duplicated under any controlled condition. Nevertheless, mobile phone manufacturers and gas stations ask users to switch off their phones. One suggested origin of this myth is said to have been started by gas station companies because the cell phone signal would interfere with the fuel counter on some older model fuel pumps causing it to give a lower reading. In the Mythbusters episode "Cell Phone Destroys Gas Station", investigators concluded that explosions attributed to cell phones could be caused by static discharges from clothing instead and also observed that such incidents seem to involve women more often than men. Most fueling is done in the open air, therefore it is not often an explosive concentration of vapors is present.
The U.S. National Fire Protection Association does most of the research and code writing to address the potential for explosions of gasoline vapor. The customer fueling area, up to 18 inches (46 cm) above the surface, normally does not have explosive concentrations of vapors, but may from time to time. Above this height, where most fuel filler necks are located, there is no expectation of an explosive concentration of gasoline vapor in normal operating conditions. Electrical equipment in the fueling area may be specially certified for use around gasoline vapors.
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