Diesel Exhaust Fluid, or DEF, is a non-toxic, non-hazardous, and non-flammable additive required by most diesel engines built after 2010. It is made of 32.5% synthetic urea and 67.5% de-ionized water.
In 2004, the EPA passed tighter emission standards that would require new engines to reduce emissions of particulate matter and smog-forming compounds by 2010. To meet these requirements, most manufacturers of heavy-duty diesel trucks turned to Select Catalytic Reduction (SCR) technology.
SCR technology has been used since 1957 to reduce emissions of coal-fired power plants and similar stationary sources. It was first adapted to diesel trucks by Nissan in Japan in 2004 to satisfy the strictest emission standards of the time. It was natural for the majority of US manufacturers to adopt the tried technology to meet 2010 EPA standards. In fact, the lone manufacturer that looked to other systems to meet the new standards began to implement them after 2013, demonstrating that SCR technology was the most effective known method to lower emissions without sacrificing engine performance.
To lower emissions, SCR systems use the heat from the engine as a catalyst and inject a mixture of urea and water into the exhaust stream, converting harmful nitrogen oxides (NOx) into nitrogen and water vapor -- two harmless gases that naturally exist in the air we breathe.
DEF technology reduces the NOx and particulate matter from diesel engine exhaust by 90% and has significantly lowered harmful emissions from the trucking sector.
NEXGEN DEF founders were already Northwest leaders in bulk fuel transport when the new EPA emission standards of 2010 took effect. We recognized that there was not a sufficient supply of quality DEF to meet the demand that would come with the increased adoption of SCR technology in diesel trucks.
Without a regular stream of DEF, it would make it impossible for our customers to conduct business. To ensure that they had a reliable source for high-quality DEF, we began to produce, not just transport, DEF product in Portland, Oregon.
We began by sourcing our urea prill, which is automotive grade urea in pellet form, to use in our proprietary solution. We then built out a state-of-the-art, American Petroleum Institute certified facility to manufacture and distribute our DEF, under a new business line: NEXGEN Products.
NEXGEN DEF is now the largest provider of diesel exhaust fluid (DEF) in the Pacific Northwest. with plants in Portland and SeaTac, Washington. Our plant in SeaTac produces a million gallons per month, allowing us to serve Seattle and western Canada. In 2021, we'll begin producing NEXGEN DEF in a plant in Tampa, Florida.
Our latest step has been to bring our product to the pump by adding NEXGEN DEF dispensers to an increasing number of Cardlocks throughout Oregon, making it easier than ever to access the latest in diesel system innovations.

Unlike some emission-reducing technology, SCR systems utilize an “after-treatment” process to control emissions outside of the engine. That means manufacturers are able to tune engines to their optimal performance and fuel efficiency. This not only decreases NOx emissions, it allows your engine to deliver more horsepower without burning an extra drop of fuel. When compared to 2007 vehicles of similar engine specifications, early customers of trucks with SCR systems reported a fuel savings of 5% and higher.
Because they reduce particulates, the SCR/DEF process also increases the time between required cleaning of the diesel particulate filter (DPF). The DPF captures any remaining particulates in the exhaust before it is released. DPF filters are expensive and require significant down-time when it’s time to clean them. Less frequent cleaning of the DPF further reduces the costs of maintaining a diesel engine on a per-gallon and per-mile basis.
NEXGEN DEF uses an automotive-grade, synthetically produced urea with a natural pH of 9.0 — about the same as household baking soda. It is more stable and less toxic than agricultural urea, which is a common ingredient in fertilizers. 90% of the world’s urea is allocated for agricultural use.
If a substandard agricultural-grade urea were to be used in DEF, it would significantly damage your SCR system, eventually causing the truck to break down.
Of all the fluids used in your vehicle -- diesel, engine oil, anti-freeze, etc -- DEF is the least hazardous. It is not toxic, harmful or dangerous, but you should still follow common sense practices when handling DEF.
If it comes in contact with skin, wash the area with soap and water. If small incidental spills occur on surfaces, simply wash away with water. Left to dry, DEF will form white crystals which can be washed away as well. It can stain clothing and be corrosive to certain metals such as carbon steel, aluminum and copper.
You may note the slight smell of ammonia when filling your vehicle. With normal use, this is not harmful. However, if a large spill occur or spills in areas without ventilation, and you inhale the fumes, move to an area of fresh air. If you experience continued symptoms like irritation of your throat, consult a doctor.
DEF should not be consumed. Consult a doctor immediately if swallowed.
SCR technology reduces the release of NOx particulates by 90% compared to typical diesel engines prior to 2010. It also increases fuel efficiency roughly 5%.
When SCR systems are combined with other smart technology -- like diesel particulate filters and 100% renewable diesel -- heavy-duty trucks can operate with near zero emissions.
HEAT
DEF should be stored below 86 degrees Fahrenheit and out of direct sunlight.
COLD
Your vehicle's SCR system should operate normally in cold weather. DEF is roughly 2/3 water and has a freezing point of 12 degrees Fahrenheit and -11 degrees Celsius. However, most SCR systems have built-in heat functions to accomodate. If the DEF in your tank freezes, it should start normally. Once your truck is started, the SCR system will begin the thawing process. As water expands when frozen, it is best practice to leave some room in your DEF tank during low temperatures.
Never add antifreeze or other additives to your DEF. For your SCR system to work, it is critical that your DEF be free from impurities with an exact water-urea ratio. Additives will not only compromise the SCR system, they can cause significant and costly damage to your vehicle.
NEXGEN DEF offers insulated tanks with heat elements to prevent freezing during storage.