New tractors, excavators, cranes and other mobile engines that run on diesel, but not on roads, are equipped with SCR technology, which requires DEF.
SCR technology and DEF for NOx reduction is now common in several types of non-road engines, eg:
- Agriculture / farm engines such as tractors and combine harvesters
- Mobile cranes
- Engines used in harbours and airports
- Excavators and engines used in mines or construction