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Federal Emission NOx Standards for New Engines
lTier 1 – 3, compliance
met with engine design (mostly)
lTier 4, further 90+%
reduction over Tier 1 – 3
hp
> 750
(except
gensets > 900 kW)
Gensets
> 900 kW (1207 hp)
Tier 4 NOx Emission Standards
*Districts in
nonattainment areas (CA, Northeast, ATL) may impose more stringent
standards for new and existing engines.