Bird on a car: what does fuel marking mean?

Often at gas stations or on the gas tank flap, drivers notice strange symbols that resemble stylized images of birds or wings. These symbols, commonly referred to simply as “birds,” are not just a decorative design element.

In fact, this is an important element of the international marking system EN 16942, which is designed to eliminate errors when refueling a car. Understanding what it means bird on the car, can save your vehicle's engine from costly repairs.

The introduction of these designations was a response to global changes in the fuel and lubricants market and the emergence of new types of fuel, such as biodiesel and ethanol blends. Now every driver should be able to read these codes to be sure of the correct choice.

EN 16942 standard and new designations

A common labeling system has been introduced in the European Union and many other countries to harmonize fuel type designations. Previously, the names of gasoline and diesel engines could differ from country to country, creating confusion for travelers.

Now all types of fuel are divided into three main groups, each of which has its own unique geometric symbol, reminiscent of a wing or a bird. Inside these figures are letters and numbers indicating the chemical composition and octane number.

The main purpose of introducing the standard is to prevent errors during refueling, especially in the context of international logistics and tourism. Marking It is applied not only to fuel dispensers, but also to car fuel tank caps.

• 🔵 Circle - indicates gasoline of various brands.
• ⬛ Square - used for diesel fuel.
• 🟢 Diamond - designed for gaseous fuels.

Ignoring these symbols may result in inappropriate substances entering the tank. For example, refueling with gasoline instead of diesel will cause instant failure of the high pressure fuel system.

Petrol markings: round symbols

If you see a circle on the gas filler flap, it means your car runs on gasoline. Latin letters are located inside the circle E or E5, E10, E85.

Letter E comes from the word Ethanol (ethanol), and the number indicates the maximum percentage of bioethanol in the mixture. This is critical information for modern engines, sensitive to fuel quality.

Most modern cars are adapted to use fuel with an ethanol content of up to 10%. However, older models or specific engines may require strict proportions.

Using fuel with a higher ethanol content than permitted by the manufacturer may attack the rubber seals and plastic parts of the fuel system. Therefore the number inside the circle is the maximum permissible value, not a mandatory requirement.

You can use fuel with less ethanol than specified, but not more. For example, if a car is rated for E10, then E5 will not harm it, but E85 can cause serious problems.

Diesel symbols: square signs

For diesel fuel, a square symbol shape is used. Inside it you can find the notation B7, B10, B30 or B100. Letter B comes from Biodiesel.

The number indicates the percentage of biodiesel (methyl esters of fatty acids) mixed with regular diesel fuel. The standard fuel at most gas stations is B7, containing up to 7% bioadditives.

There are also special markings for winter diesel or arctic grades, which may have additional letter indices such as D (Diesel) or climate designations.

• 🚜 B7 is the standard diesel fuel for passenger cars.
• 🚛 B10/B30 - fuel for heavy equipment and trucks.
• ❄️ B7 (Winter) - winter version with improved properties.

⚠️ Attention: Never put pure biodiesel (B100) into a regular passenger vehicle unless specifically permitted by the manufacturer's instructions. This may cause the rubber tubes to dissolve.

It is important to monitor the cleanliness of diesel fuel, since bioadditives can contribute to the proliferation of microorganisms in the tank during prolonged inactivity. The use of high-quality filters and additives is becoming a prerequisite for operation.

Gaseous fuels and other types

Diamond-shaped signs are designed for gas fuel, which is gaining popularity due to its environmental friendliness and efficiency. Inside the diamond are letter codes indicating the type of gas.

The most common designations CNG (Compressed Natural Gas) for compressed natural gas and LNG (Liquefied Natural Gas) for liquefied natural gas. There is also a marking LPG for propane-butane mixture.

Gas equipment requires special attention to the quality of the refilled substance. The presence of impurities or incorrect pressure can cause the gearbox to operate incorrectly.

Why is gas cheaper than gasoline?

The gas has a higher octane number and burns more evenly, which reduces knocking. However, its energy density is lower, so the consumption in liters (or kilograms) may be higher.

Owners of cars with LPG should regularly undergo system diagnostics. Tightness of connections and the serviceability of the valves is the key to safe operation of a vehicle on gas.

Color coding and additional symbols

In addition to the geometric shape, the color of the sticker or nozzle of the refueling device plays an important role. Although the EN 16942 standard focuses on black and white images, in practice color is often used for quick identification.

The color green is traditionally associated with environmentally friendly fuels or gas. Red is often used to denote leaded gasoline (which is now virtually unheard of) or specific oils.

Additionally, pictograms may be used to indicate the need to use additives or special storage conditions. For example, the water drop symbol can warn that the fuel is sensitive to condensation.

Symbol	Fuel type	Description	Where is it found?
Circle E5/E10	Gasoline	With ethanol content up to 5-10%	Passenger cars
Circle E85	Bioethanol	High alcohol content	Flex-F auto
Square B7	Diesel	Standard diesel fuel	Diesel cars
Diamond CNG	Methane	Compressed natural gas	Car with HBO

Visual perception of color helps you quickly find your way in the dark or in poor lighting at a gas station. However, you cannot rely on color alone as color standards may vary from region to region.

Practical tips for refueling

When approaching the pump, first of all pay attention to the sticker near the gas tank flap. Compare the image on the vehicle with the markings on the gun. They must completely match in shape and letter designation.

If you are driving a rental car in another country, do not hesitate to ask the gas station attendant again. The language barrier should not become an obstacle to proper refueling.

If you make a mistake and fill with the wrong fuel, do not start the engine under any circumstances. If you have already started the car and feel strange in its operation, stop immediately and call a tow truck.

Timely contacting the service will minimize the damage. Flushing the tank and replacing filters will cost less than overhauling the engine or replacing fuel injectors.

Frequently Asked Questions

Is it possible to mix gasoline with different ethanol contents?

Yes, modern engines are capable of running on a mixture of gasoline with different ethanol contents, if the final concentration does not exceed the permissible limit for a given engine. The electronic control unit will adjust the fuel supply.

What to do if the gas station does not have the required markings?

If the EN 16942 marking is missing, rely on the traditional names (AI-95, DT) and the color of the gun, but be sure to check with the gas station operator about the composition of the fuel, especially if you are abroad.

Does ethanol harm older cars?

High ethanol content can be corrosive to rubber and plastic parts of the fuel system of older cars produced before the widespread introduction of biofuels. They are advised to use fuel with a minimum alcohol content.

Where can I see the complete table of markings?

Full correspondence tables and interpretations are available on the official websites of car manufacturers, as well as on information stands of large oil and gas companies and in applications for finding gas stations.