Diesel Exhaust Fluid

What is Diesel Exhaust Fluid?

Diesel Exhaust Fluid Diesel Exhaust Fluid is the mixture of high purity synthetic urea and deionized water that is used in Selective Catalytic Reduction (SCR) systems on diesel engines. Diesel Exhaust Fluid is injected into the exhaust stream via  controlled dosing module where the water vaporizes leaving ammonia molecules free to travel into catalytic converter where it reacts and neutralizes the NOx molecules, converting it to nitrogen and water.

How it Works

Diesel Exhaust Fluid is carried onboard SCR-equipped vehicles in specially designed tanks and is dosed into the SCR system at a rate equivalent to 2-5% of diesel consumption. This low dosing rate ensures long refill periods, and the use of Diesel Exhaust Fluid helps improve fuel economy allowing fleets to realize a reduction in overall operating costs.

Committed To Quality

SC systems are sensitive to potential chemical impurities in the urea solution. Therefore, it is essential to maintain high standards of diesel exhaust fluid quality and ISO standard 2224-1 is in place to insure fluid quality. Diesel Exhaust Fluid is manufactured in accordance to these strict standards giving you the peace of mind you need using it in your SC System.

Why Now?

In 2010 the Environmental Protection Agency, OEMs, and many trucking fleets have committed themselves to a cleaner environment by reducing NOx emission. To reduce NOx emissions, most new trucks will be equipped with a Selective Catalytic Reduction (SCR) system. The SCR technology requires the use of diesel exhaust fluid (DEF)

Old World Industries, one of North America’s largest suppliers of functional fluids, has the existing supply chain of 10 production locations and over 4,500 distribution points to make Diesel Exhaust Fluid Diesel Exhaust Fluid available to you. This is Old World’s commitment to a cleaner environment. With Diesel Exhaust Fluid Diesel Exhaust Fluid. “Blue Means Go.”


Storage temperature between 40º F and 80º F is recommended to maintain shelf life. Storage temperature above 12º F is recommended to avoid crystallization, which starts at 11º F. Prolonged storage above 86º F will cause hydrolysis to occur, with the consequent formation of ammonia and pressure rise, and will reduce shelf life.

Frequently Asked Questions

What is Diesel Exhaust Fluid?

Diesel Exhaust Fluid Diesel Exhaust Fluid is the reactant that is used in Selective Catalytic
Reduction(SCR) systems on diesel engines. When used in an SCR system, Diesel Exhaust Fluid will
reduce the levels of NOx emissions of those engines.

What is SCR?

SCR is an acronym for Selective Catalytic Reduction. It is a catalyst installed on the
exhaust system of a diesel truck. It sprays DEF into the exhaust stream to mix with
exhaust gases to convert to nitrogen and water.

What is Diesel Exhaust Fluid made of?

Diesel Exhaust Fluid is a high-purity, 32.5 strength urea solution and deionized water.

Diesel Exhaust Fluid is a high-purity, 32.5 strength urea solution and deionized water.

Yes, It needs to meet the ISO 22241-1 quality standard.

Does it need to meet any quality standards?

No, Diesel Exhaust Fluid is not hazardous.

Is it hazardous?

The EPA has mandated the reduction of NOx emissions by the end of the 2010.

What has changed to make Diesel Exhaust Fluid necessary?

Diesel Exhaust Fluid is stored in a designated tank on the vehicle. It is then replenished like fuel.

How will Diesel Exhaust Fluid mix with fuel?

No, It is not an additive. It is sprayed into the exhaust stream where it is hydrogenated
before the catalytic converter effects the breakdown into nitrogen and water.

How much Diesel Exhaust Fluid will I need?

Diesel Exhaust Fluid is consumed at a rate of approximately 2 – 5% by volume to diesel consumption.