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Wheels of Wisdom: Understanding Diesel Exhaust Fluid (DEF)

Calling all experts in diesel engines and emission reduction! We need your expertise on Diesel Exhaust Fluid (DEF) and the systems that use it. Help us explore this revolutionary solution and its environmental impact. Share your knowledge and join the discussion today!

July 6, 2023
Wheels of Wisdom: Understanding Diesel Exhaust Fluid (DEF)

What have you learned about Diesel Exhaust Fluid (DEF) and its impact on your school transportation fleet?

Image: Canva

2 min to read


In an era where environmental consciousness is often discussed when it comes to school buses, the need for cleaner and greener technologies has become paramount. One such innovation is Diesel Exhaust Fluid (DEF), a solution that significantly reduces harmful emissions produced by diesel engines.

What is Diesel Exhaust Fluid (DEF)?

DEF is a non-toxic, colorless liquid composed of 32.5% urea and 67.5% deionized water. It is a key component in Selective Catalytic Reduction (SCR) systems, which are installed in diesel vehicles (such as school buses) and heavy-duty machinery to meet stringent emission regulations. DEF is injected into the exhaust stream, where it undergoes a chemical reaction to convert harmful nitrogen oxides (NOx) into nitrogen, water vapor, and trace amounts of carbon dioxide.

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The Role of DEF in School Bus Emission Reduction

DEF plays a vital role in reducing nitrogen oxide emissions, which are major contributors to air pollution and smog formation. By using DEF and SCR systems, diesel school buses can achieve a significant reduction in harmful emissions, resulting in cleaner air and improved public health. This eco-friendly solution has gained popularity across various industries, including transportation, agriculture, construction, and more.

Share Your DEF Wisdom

We value the insights and experiences of our readers when it comes to using DEF and SCR systems. If you have hands-on knowledge or expertise in this area, we invite you to share your thoughts with us. How has DEF impacted your diesel engines? Have you noticed a significant reduction in emissions? What challenges or benefits have you encountered while using SCR technology? Your valuable input will not only enrich our discussion but also provide real-world perspectives on the effectiveness and practicality of DEF and SCR systems. Join the conversation and help us deepen our understanding of this eco-friendly solution.

FROM THE ARCHIVES: Getting the Most Out of DEF

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