What is AdBlue® ?

Simply put, AdBlue® is a 32.5% solution of urea in deionised water and is required by many commercial vehicles operating on Europe's roads. AdBlue® is essential for the correct operation of an advanced pollution control technology installed in the exhaust system called Selective Catalytic Reduction or SCR. Unlike diesel, AdBlue® is a clear, non-toxic liquid that is safe to handle and does not damage the environment. AdBlue® is not a fuel or fuel additive.

AdBlue® is a high specification solution and is manufactured to the DIN 70070 and ISO 22241 standards.

Who needs AdBlue® ?

Currently, AdBlue® is required by the majority of heavy duty diesel vehicles (trucks, buses and coaches) purchased after October 2006.

In order to meet the Euro IV and V emissions limits, all of the major European truck makers, to greater or lesser extent, offer SCR equipped vehicles. However, MAN and Scania have a firm focus on an alternative technology called EGR that does not require the use of AdBlue® and have equipped the majority of their model ranges accordingly.

It is important to ensure that the vehicles remain supplied with AdBlue®, as an on-board policing system will enforce a torque penalty if the AdBlue® tank is empty. This is to ensure that the vehicles NOx emissions remain below the legal limit.

What is SCR ?

SCR, or Selective Catalytic Reduction, is an emissions control technology first employed on coal-fired power stations to clean oxides of nitrogen (NOx) from the exhaust gasses. In 2006, the technology successfully crossed into the European heavy-duty diesel market, where it enabled trucks to meet the Euro IV and V limits.

An SCR system uses AdBlue® and a vanadium or base metal catalyst mounted in the vehicle's muffler to reduce NOx to water vapour and atmospheric nitrogen. This reaction takes place downstream of the engine in the exhaust system and is known as "after-treatment". Unlike the alternative EGR technology - championed by MAN and Scania - SCR tackles the problem

outside of the engine and has the potential to achieve >80% NOx reduction rates, allowing the engine to be tuned for maximum efficiency. Having the engine set up for maximum efficiency allows for an estimated fuel saving of 3-5%, giving operators the opportunity to save thousands on their annual diesel fuel bills.

SCR models only

  • Daimler (Mercedes)
  • DAF
  • Iveco
  • Renault Trucks

EGR & SCR models available

  • MAN
  • Scania
  • Volvo

What are Euro IV and V?

The European Commission sets the limits for harmful pollutants - including NOx and particulate matter (PM) - within its Euro IV and V legislation. The legislation is binding and limits the emissions of all vehicles >3.5t registered after the implementation date. Euro IV was implemented in 2006 and Euro V in October 2009. All new registrations within the European Union must meet Euro V emissions standards.

Where can I buy AdBlue® ?

AdBlue® can be purchased by the haulier on the road at a truck stop, service station or manufacturer dealership. It is also possible to arrange for a supply of AdBlue® direct to the haulier's base of operations. You can use Find AdBlue®.com to find the nearest AdBlue® supply point and information about home base AdBlue® supply. FindAdBlue.com has details of over 10,000 AdBlue® supply points throughout Europe.

While the price of AdBlue® is lower when purchased in bulk at the home depot, this method can incur costly installation and equipment fees. In fact, some operators prefer the convenience of roadside AdBlue® refilling. Indeed, AdBlue® refilling is often linked to the operator's diesel refuelling strategy.

AdBlue® is used by the SCR system at a rate equivalent to 5% of diesel consumption and is currently less than half the price of diesel, per litre.

On-the-road supply methods


Canisters are available from over 5000 service stations, supply depots and manufacturer dealerships around Europe. This supply type is typically used in an emergency situation and due to the small size there is a cost premium. Available sizes include 5L, 10L and 18L.


Retail pumps supply AdBlue®, by the litre, at a growing number of locations throughout Europe. Indeed, following a period of investment by the oil industry, some truck stops have installed AdBlue® pumps on all diesel islands and it is now possible to refill with AdBlue® while refuelling with diesel.

Home-Depot Supply Methods


Intermediate Bulk Containers (IBCs) are a standardised method of storing and transporting liquids used in the chemical industry. IBCs hold 1000L of AdBlue® and are competitively priced in comparison to on-the-road supply methods. Also, IBCs do not require permanent installation, and are currently one of the most popular options for the haulage industry.


A mini-bulk system is a fixed installation at a haulier's home depot. Typically mini bulk systems have a capacity between 4000-7000L and require regular refilling by an AdBlue® producer. Due to the quantity of AdBlue® purchased, cost/litre is low compared to other methods. However, the equipment is expensive and requires installation and maintenance.

Storage and handling

It is essential that the purity of AdBlue® is ensured throughout the supply chain and when stored at a home depot. Therefore, it is critical that AdBlue® is transported and stored in a manner that conforms to the CEFIC guidelines. When stored at a home depot, it is important that the AdBlue® is not decanted from IBCs or bulk containers into smaller canisters as SCR catalysts are sensitive to many contaminants - especially mineral ions - and can suffer irreversible damage. If the damage has resulted from mishandling of AdBlue®, the vehicle's warranty is likely to be found invalid.

To some extent AdBlue® is sensitive to extreme temperatures, both hot and cold. The solution will freeze if its temperature falls below -11°C, and the urea content can decrease if stored at temperatures in excess of 30°C. However, AdBlue® is not harmed by the freezing process and once thawed will retain its concentration and quality. In areas where the temperature is frequently in excess of 30°C (Greece, Spain etc.) it is necessary to ensure that the solution is not stored in direct sunlight.

The trucks themselves, and larger equipment installations, are built with several heated components to minimise the problem of frozen AdBlue®.

Can I Make my own AdBlue?

No. AdBlue® is a high purity chemical solution manufactured to a strict specification and distributed through a secure supply chain. It is highly unadvisable to attempt to create your own 32.5% urea solution from fertilizer grade urea and water-purified or otherwise.

Remember - using a non DIN/ISO specification urea solution will probably result in catalyst damage, invalidating the vehicle's warranty!