SCR

SCR stands for "Selective Catalytic Reduction." It is an emission control technology used in diesel vehicles to reduce nitrogen oxide (NOₓ) emissions. In an SCR system, a reducing agent—typically a urea solution known as Diesel Exhaust Fluid (DEF)—is injected into the exhaust stream. Under high temperature conditions, the urea decomposes into ammonia (NH₃). With the help of a catalyst, the ammonia reacts with NOₓ in the exhaust, converting it into harmless nitrogen (N₂) and water (H₂O), thereby significantly reducing harmful emissions.