NECA
Nitrous Oxide Emission Control Area are sea areas with regulated nitrous oxides (NOx) emission caps.
Current NECA areas (as on 2023) are North American ECA and US Caribbean sea.
As per MARPOL Annex VI, Regulation 13, this regulation shall apply to:
(i) each diesel engine with a power output of more than 130 kW which is installed on a ship constructed on or after 1 January 2000;
(ii) each diesel engine with a power output of more than 130 kW which undergoes a major conversion on or after 1 January 2000.
This regulation does not apply to:
(i) emergency diesel engines, engines installed in lifeboats and any device or equipment intended to be used solely in case of emergency;
(ii) engines installed on ships solely engaged in voyages within waters subject to the sovereignty or jurisdiction of the State the flag of which the ship is entitled to fly, provided that such engines are subject to an alternative NOx control measure established by the Administration.
Given below is the emission requirements that each vessel has to follow while in any of the NECA areas:
Here above, N = n = Number of revolutions made by the engine per minute ( or RPM).
The above table denotes the maximum limit for NOx emission while in the NECA areas. Ships have to follow the limits add pet the tier in which they fall. For example, A vessel built in 2022 with its engine RPM less than 130 can emit a maximum amount of NOx 3.4 g/KWH and so on.
