What is AdBlue®?

AdBlue is used to reduce NOx emissions in vehicles equipped with SCR technology

AdBlue converts harmful NOx from your diesel vehicle exhaust into harmless nitrogen and steam, therefore considerably reducing the emissions of nitrogen oxides (NOx) that are a major source of atmospheric pollution and that lead to smog in urban centres. According to studies done by the World Health Association, NOx emissions are known to aggravate asthma.

Since 2005, legislation on diesel vehicles in the UK & Ireland and in the rest of Europe demands a drastic reduction of NOx emissions. Vehicle manufacturers, and first and foremost those of large goods vehicles, have had to re-think the exhaust system on their vehicles. More and more diesel cars, tractors and other off-road vehicles are also now equipped with the SCR system in the exhaust.

Passenger Car Drivers - for where to buy AdBlue tips and advice, please see our dedicated advisory pages for private car owners. Business owners wishing to retail AdBlue – read about why Yara’s AdBlue should be your first consideration.

Practical tips
Practical tips

Practical tips

AdBlue is very easy to use and is a harmless substance. It is not a fuel, nor a fuel additive but a high purity urea solution that must be used in a dedicated tank on your vehicle, that should just be refilled as and when required. AdBlue is non-flammable and non-explosive. It is classified as a transportable fluid with minimal risk. If you ever spill AdBlue on your hands, simply wash them thoroughly with water. Learn more about how to use AdBlue:

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What is SCR technology for trucks, buses, off-road vehicles and cars?

"SCR" is the name of a post-combustion technology treatment for diesel vehicles, which allows them to reduce their harmful emissions of NOx (nitrogen oxides). SCR stands for Selective Catalytic Reduction. This technology requires the use of a reagent called AdBlue. Almost all of the main engine manufacturers use this technology to meet the requirements of new legislation on NOx (Nitrogen oxides) emissions.

The main components of the SCR system are the:

  • SCR catalyst
  • AdBlue Fluid injection unit
  • AdBlue tank
  • AdBlue injection control unit.

How does AdBlue work with SCR technology?

AdBlue is injected from the vehicle’s dedicated AdBlue storage tank into the exhaust pipe, which is in front of the SCR catalyst, but downstream of the engine. As it is heated in the exhaust, the AdBlue changes into ammonia (NH₃) and carbon dioxide (CO₂). When the nitrogen oxide (NOx) gases from the exhaust pipe react inside the catalyst with the ammonia, the harmful NOx molecules in the exhaust are converted into harmless nitrogen and water, which is released to the atmosphere as steam.

Do I need to maintain my vehicle’s SCR system?

The SCR system is installed in your vehicle by the manufacturer and works automatically. You do not need to maintain or modify it. AdBlue is automatically injected into the exhaust depending on your vehicle engine’s load. As for adjusting the consumption, the level of AdBlue consumption is determined by the vehicle manufacturer.

To make sure that your SCR system works correctly, please make sure that you only use high quality AdBlue, such as that sold under the brand name Air1 by Yara. This will protect the investment you have made in your vehicle as a low quality reagent would not be pure enough and could be contaminated with impurities. This could cause damage to your catalyst and lead to very high repair costs, that the vehicle manufacturer will not cover.

Yara's AdBlue is marketed under the Air1 brand. Air1’s AdBlue is produced from a high purity urea solution. Urea is produced synthetically from ammonia and CO₂ (carbon dioxide), from which Air1’s AdBlue is extracted directly as “hot melt” urea, which is a different process to fertilizer grade urea. This AdBlue process is quality assured to ensure the correct, stringent specification is attained, ensuring the quality and purity of Yara’s Air1 AdBlue. Learn more about the importance of the quality of AdBlue.

Use quality AdBlue: Yara’s Air1® brand

AdBlue is used in SCR technology-equipped diesel vehicles. Yara is one of the world’s leading producers of AdBlue, with its Sluiskil plant in the Netherlands being the largest AdBlue production site in the world. Yara’s brand of AdBlue, Air1, is supplied through its network of Air1 distributors in the UK & Ireland.