AdBlue® (Diesel Exhaust Fluid (DEF)) is a solution of synthetically produced urea in de-mineralized water which is used to reduce the emissions of nitrogen oxides from the exhaust systems of diesel vehicles. The average consumption of AdBlue is approx. 5 % of the diesel consumption. It is injected into the exhaust system of heavy diesel vehicles constructed according to norm EURO VI. These vehicles are equipped with a dedicated AdBlue® tank which requires special equipment for the refilling.