Frequently Asked Questions

AdBlue is a highly purified colorless liquid. It contains demineralized water and urea (32.5%). AdBlue is used with diesel engines and is also known outside of Europe as DEF, ARLA 32 or AUS 32.

The main active component of AdBlue is ammonia. This is chemically formed by hydrolising automotive urea, which is the main raw material for AdBlue. Urea is also used in the production of fertilizers and many more applications.

AdBlue is used with diesel engines using SCR technology. This technology (Selective Catalytic Reduction) reduces harmful emissions (NOx).

AdBlue is injected into the catalyst of the SCR system, where it triggers a chemical reaction with the ammonia. This chemical reaction converts the toxic nitrogen oxides (NOx) into nitrogen (N2) and water vapor (H2O).

Water vapor and nitrogen are naturally occurring gassesthat are harmless to the environment

If you use a modern diesel powered machine fitted with an SCR catalyst, you will need AdBlue.
Based on the current developments in engine technology, if you run a diesel engine you will still need NOx reducing fluids in the future.

Emission legislation for transportation and off-road vehicles will become more demanding. Euro 6 (due in2014) will require the use of SCR technology and AdBlue for all transportation vehicles and passenger cars. So it is likely that you will require AdBlue in the future.

As a fleet owner you will also need AdBlue for your replacement vehicles. Since 2006, most newly built trucks and buses are fitted with an SCR system that uses AdBlue. Putting new trucks into use will automatically require you to familiarise yourself with AdBlue. Current developments also point towards an increase in the use of catalytic reduction in off-road vehicles. Stage I to IV (emissions legislation due in 2014) demand cleaner off-road vehicles with lower NOx output. AdBlue is the best way to achieve this.

2014 will also change the diesel technology in passenger cars. SCR and AdBlue will become a standard feature for diesel driven cars, which will make AdBlue a part of daily life.

Your vehicle needs AdBlue to reduce NOx output. Due to the increasingly stringent emission legislation, diesel engines need to run more cleanly. NOx standards have sharpened for transportation vehicles, as well as off-road vehicles and passenger cars.

All commercial vehicle manufacturers have to meet the Euro 5 and Euro 6 standards for diesel engine emission. Although Euro 5 emission standards could be met by different technologies, Euro 6 standards (into force January 2014) require the use of Selective Catalytic Reduction with AdBlue.

The Euro 1-6 emission legislation applies to motorcycles, heavy duty vehicles (buses, trucks) and passenger cars. However, not all vehicles are required to meet the same standards.

Stage I to IV legislation applies to most off-road machinery as used in construction, for farming and other applications. Whether you need to use SCR technology and AdBlue accordingly, depends on the emission levels of your machine or vehicle.

More information on the appliance of legislation on your vehicle can be obtained from the manufacturer.

Your AdBlue consumption depends on your type of operation. A full tank of AdBlue will last several tanks of diesel.
The average use of AdBlue vs diesel for tucks is 4 to 8%.

Local distribution: – Approximately 500L in one year.

  • Mid class diesel
  • (For example Opel Insignia or Peugeot 508):
  • 1 llitre AdBlue for 1,000 km
  • SUV/MPV class diesel
  • (for example Opel Zafira or VW touran): -5 litre AdBlue for 1,000 km


Because of the wide variety of off-road vehicles, it is difficult to pinpoint their exact usage. A large heavy duty tractor can use 2,500L of AdBlue a year. A ratio of 5 to 10% of the diesel usage is used to calculate the required AdBlue.

Look for the AdBlue logo and a green and blue checkerboard pattern:

AdBlue should always be a colorless clear liquid. If you buy drums or cans, watch out for brand names that are similar to AdBlue. You could be dealing with a brand of inferior quality. Make sure that you buy AdBlue from a VDA licensed partner and look for this text on the container or dispensing system: “AdBlue according ISO 22241”. You can also look for the GreenChem logo

Water that in Adblue is not the water you drink every day. This water is de-mineralized or de-ironized to make it “pure water”.Making Adblue is more complicated than simply adding urea to water.

The urea used is manufactured specifically for the production of AdBlue. Few suppliers can produce the high-quality urea needed to ensure AdBlue complies to the stringent ISO 22241-1 specification.

That was the technical part!! In practice, AdBlue® is a solution that helps to clean up the NOx particles that your Diesel’s Car, Van, Truck or Bus releases into the air.

No, the engine will not be damaged when you run out of AdBlue. You can continue to the next AdBlue distribution point or use your emergency supply at the next stop. However the engine performance could be effected until you fill up.

No, the engine will not shut down, but some engines automatically limit engine performance when AdBlue supplies are depleted. If your engine is equipped with SCR technology, your vehicle will lose power, and reduce its emission according to legal standards. The vehicle’s performance will be restored when AdBlue levels are up again.

Do not start your engine! Depending on the amount of AdBlue, you may damage your engine when you start it. You should empty and clean your tank. You will have to empty the whole tank and discard the mixture.

For further instructions on emptying and cleaning your tank, please contact your vehicle supplier.

You can recognise your AdBlue tank by its blue cap or an AdBlue label, but it is a totally separate tank.

The filling point is often fitted near your diesel cap. Some passenger cars have an AdBlue tank in the boot or in the engine bay.

The opening for your AdBlue tank is narrower than the opening for a diesel tank, so you should not be able to put diesel in the wrong tank (the nozzle does not fit).

AdBlue is not dangerous to the environment. A small AdBlue spill can be diluted with water. It is best to mop up the spillage and avoid flushing it down a drain or waterway. In case of a large spill, try to prevent the spillage from entering drains or waterways. Contain the spill with sand, earth or your spill kit and dispose of it properly.

Spill kits are available in different sizes and sets.

Note: The surface on which you spill AdBlue may become slippery. Make sure that you clean up the spill as quickly as possible to prevent slipping and falling.

No, never try to reuse spilled AdBlue! Spilled AdBlue will always be contaminated. Using contaminated AdBlue can cause costly damage to your vehicles’ SCR system, so no matter how great the spill, you cannot reuse it .

If you’re driving a newer diesel car, chances are it comes with AdBlue technology. It won’t be obviously advertised, but manufacturers like Volkswagen, Audi, Range rover,Toyota,Renault, BMW,Opel,Man, Mercedes, Peugeot, Citroen, Jeep Cherokee and Jaguar all feature AdBlue technology.

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