A summary of current and near-term regulations is listed below.
EPA - The United States Environmental Protection Agency (EPA) regulates exhaust emissions from diesel engines installed on U.S. flagged / registered marine vessels.
EU - The Nonroad Mobile Machinery Directive (Stg IIIa) regulates exhaust emissions from marine propulsion and auxiliary engines used aboard inland waterway vessels operating in the European Community. The Recreational Craft Directive (RCD) regulates noise and exhaust emissions from propulsion engines used aboard recreational craft. While RCD 2 will go into effect January 18, 2016, customers can still purchase RCD 1-certified engines through 2016; check with your local Cummins professional for additional details.
IMO - The International Maritime Organization (IMO) regulates exhaust emissions on diesel engines above 130 kW (174 HP); engines used exclusively in emergency applications are exempt. IMO Tier III applies only when operating within an Emission Control Area. An ECA may be established for NOx, SOx and particulate matter, or both. The Tier III regulation will go into effect for the North America and U.S. Caribbean Sea ECAs in 2016.