How SCR Works We changed the emissions, not the engine.

Selective Catalytic Reduction (SCR) technology uses proven, existing engine architecture, a diesel oxidation catalyst and diesel particulate filter, plus SCR hardware, to meet EPA 2010 emissions standards. This allows the engine to function at optimal combustion temperatures, which increases fuel efficiency and reliability.

SCR reduces tailpipe nitrogen oxide emissions (NOx) by treating the exhaust stream with a spray of diesel exhaust fluid (DEF). DEF, along with the exhaust heat and a catalyst, converts NOx into nitrogen and water vapor, which are clean, harmless and present in the air we breathe every day.

It is our mission to provide reliable, durable, safe and innovative buses to our customers. And SCR technology, with its near-zero emissions, is the environmental choice to do just that.

Take a look at the diagram below to see how SCR works.