NOx Tier III

Strictest IMO NOx limit under MARPOL Annex VI Reg. 13, applying to engines above 130 kW installed on ships built on or after 1 January 2016 and trading in NOx ECAs (currently the North American and US Caribbean ECAs, with the Baltic and North Sea NOx ECAs effective 2021). Tier III is roughly 80% below Tier I. Compliance is achieved through Selective Catalytic Reduction (SCR), Exhaust Gas Recirculation (EGR), or LNG dual-fuel operation; engine builders certify and class verifies onboard.