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Diesel Exhaust Fluid - DEF - what is it?

Diesel Exhaust Fluid (DEF) is a high quality urea solution that is easy to use

Diesel Exhaust Fluid (DEF) is 32.5% solution of high-purity urea in de-mineralized water that is used with the Selective Catalytic Reduction system (SCR) to reduce emissions of nitrogen oxides (NOx) from the exhaust systems of diesel vehicles in the USA. Diesel Exhaust Fluid (DEF) is clear non-hazardous liquid.  It is not a fuel, nor a fuel additive and needs to be filled into a dedicated Diesel Exhaust Fluid (DEF) tank which is on your diesel vehicle. It is replenished in a similar way to refueling diesel. Should you spill Diesel Exhaust Fluid (DEF) on your hands, simply wash it off with water.  Click here for a Diesel Exhaust Fluid MSD for the USA.

Diesel Exhaust Fluid (DEF) - where can I order it from?

Diesel Exhaust Fluid from Air1 can be found at truck stops across North America and at USA Diesel Exhaust Fluid Distributors who are also established distributors of fuel and lubricants for diesel vehicles. 

Your nearest Diesel Exhaust Fluid USA supplier from Air1 can be found here.

Diesel Exhaust Fluid (DEF) - How much do I need?

Average consumption of Diesel Exhaust Fluid is generally 3% per gallon of diesel fuel, so you will need to tank much less for DEF then you do for diesel fuel. 2.5 gallons of Air1 Diesel Exhaust Fluid will yield over 350 miles of travel.

How much does Diesel Exhaust Fluid cost?

Diesel Exhaust Fluid cost depends on the volume of your usage, and the Diesel Exhaust Fluid package that you order.  Contact us for a Diesel Exhaust Fluid price in the USA.

Diesel Exhaust Fluid storage

Diesel Exhaust Fluid needs to be protected from extreme temperatures. Diesel Exhaust Fluid's freezing point is at 12 degrees Fahrenheit (-11 Celsius). When DEF thaws, the product will retain its initial quality and vehicles will remain operational throughout the Diesel Exhaust Fluid tank thawing process. DEF should be stored in a sealed package and in a well ventilated storage area.

Why should I choose Selective Catalytic Reduction (SCR) with Diesel Exhaust Fluid (DEF) over other technologies?

Diesel Exhaust Fluid (DEF) combined with Selective Catalytic Reduction (SCR) offers you a fuel efficient solution, with lower CO2 emissions then competitive solutions to adhere to the EPA Clean Air Act.  Most North American truck manufacturers offer SCR equipped models to meet these regulations. SCR is a proven technology to reduce nitrogen oxide, that brings diesel vehicles and fleet owners a payback with low maintenance and greater fuel economy.

Diesel Exhaust Fluid (DEF) - does quality matter?

Diesel Exhaust Fluid is a very pure product.  Any contamination will affect the quality of Diesel Exhaust Fluid, and this may cause your catalyst to need expensive repairs . To prevent contamination, it is imperative that foreign materials do not come in contact with the Diesel Exhaust Fluid solution. Use dedicated Diesel Exhaust Fluid tanks and dispensing equipment.  In the USA, Diesel Exhaust Fluid from Air1 is certified by the American Petroleum Institute (API) to ensure Diesel Exhaust Fluid quality standards are maintained in accordance with ISO 22241 (ISO-22241-1, ISO-22241-2, ISO-22241-3) specifications. Buying Air1 Diesel Exhaust Fluid is a  guarantee of the correct specification required for your SCR technology.