Emissions Regulations

Tier 3/Stage III A emissions regulations required an approximate 65 percent reduction in particulate matter (PM) and a 60 percent reduction in oxides of nitrogen (NOx) from 1996 levels. Interim Tier 4/Stage III B regulations, which begin in 2011, require a 90 percent reduction in PM and a 50 percent reduction in NOx from previous Tier 3/Stage III A requirements. Final Tier 4/Stage IV regulations will be fully implemented by 2015 and will decrease NOx an additional fivefold. When all the dust settles, emissions levels for nonroad engines will be reduced 90 percent. The chart below is a good illustration of the reductions in the United States and Europe.