Frequently Asked Questions
What is DEF?
Diesel Exhaust Fluid (DEF) is a clear, non-toxic solution made up of 67.5% water and 32.5% ultra-pure urea. Urea is a nitrogen, oxygen and hydrogen compound made in huge quantities from natural gas. The DEF solution is used to convert nitrogen oxide (NOx) into nitrogen gas and water vapor. Diesel engines that have Selective Catalytic Reduction (SCR) systems use DEF to change the oxides of NOx emissions into nitrogen and water.
What is Selective Catalytic Reduction (SCR)?
SCR is the leading technology in NOx reduction for diesel engines. NOx reduction is necessary because NOx can contribute to acid rain and smog, making it harmful to our health and environment. In order to reduce NOx emissions, SCR requires a catalytic converter and a reducing agent known as Diesel Exhaust Fluid (DEF). DEF is injected directly into the exhaust upstream of a catalyst, where DEF vaporizes and decomposes to form ammonia. The ammonia then works in conjunction with the SCR catalyst to break down NOx into harmless nitrogen and water vapor.
Why Use DEF?
The 2010 EPA standard requires the use of DEF in diesel engines purchased after January 1, 2010 that use SCR systems to reduce emissions. It minimizes pollutants by making harmful emissions harmless. DEF is good for your vehicle and the environment!
Is there a Quality Standard for DEF?
Yes, DEF should be certified by the American Petroleum Institute (API). The International Organization for Standardization (ISO) has set quality requirements (22241) for diesel engines. The API Certification program ensures that Diesel Exhaust Fluid meets the specifications of ISO. Ports Petroleum sells products from manufacturers who have been certified by the American Petroleum Institute to meet the standards of ISO 22241. Ports Petroleum itself is not currently a manufacturer of these products.
What are the proper conditions for storing DEF?
DEF should be stored in a dry, well-ventilated place, out of direct sunlight. The best storage temperature for DEF is around 77°F. Long term storage should be limited, especially in high temperatures. DEF may begin to degrade over long periods of time typically over a year and at temperatures over 90°F.
What is the shelf life of DEF?
The DEF shelf life depends on storage temperature and time. When stored between 12°F to 86°F, shelf life will be over one year. However, if the maximum temperature stays below 75°F, the shelf life will be two years.
What if I accidentally spill DEF on my vehicle?
On some materials, DEF is mildly corrosive, especially on aluminum, copper and other alloys. Wash any spilled DEF off with water.
Is DEF toxic in comparison to other automotive fluids?
No, other fluids like diesel fuel, brake fluid, and even windshield washer fluid are more toxic than DEF. The EPA classifies DEF as non-hazardous. Urea is naturally occurring and is biodegradable.
How much DEF can I buy?
We sell DEF in a variety of different volumes to fit your needs, including:
• Bulk Supply
• 2.5 and 5 gallon cases
• 55 gallon drums
• 330 gallon plastic totes
If you are not sure how much DEF your company will need, look at our estimated usage table or call our DEF sales team at 1-800-562-0373.