SCR System Emissions Performance NOx reduction is achieved by injecting precise amounts of AdBlue as an aerosol spray into our unique mixing section. The AdBlue is converted to ammonia, which neutralises the nitrogen oxides to produce a harmless mixture of water and nitrogen. The AdBlue dosing is actively managed to avoid deposits and ammonia slip. The system also incorporates an extra clean up catalyst to neutralise any excess ammonia. The unique injector design, combined with an automated nozzle cleaning strategy, prevents nozzle blocking.