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California Regulations

Fuel sulphur requirements

In 2008 the California Air Resources Board (CARB) adopted a Clean Fuel Regulation for Ocean-Going Vessels within 24 nautical miles of the California coast to further reduce emissions from shipping. Since then, the permitted sulphur content of marine gas oil (MGO) and marine diesel oil (MDO) has been progressively lowered and in 2014 may not exceed 0.1%. This puts the CARB regulation one year ahead of the IMO’s 0.1% limit, which takes effect in 2015. 


CARB fuel quality requirements to limit SOx emissions
Fuel sulphur content 2009 2012 2014
CARB 0.5% MDO/1.5% MGO 0.5% MDO/1.0% MGO 0.1% MDO/MGO


At-berth emission control requirements

In December 2007, the CARB approved the "Airborne Toxic Control Measure for Auxiliary Diesel Engines Operated on Ocean-Going Vessels At-Berth in a California Port" Regulation, commonly referred to as the At-Berth Regulation. The purpose of this regulation is to reduce emissions from diesel auxiliary engines on container ships, passenger ships and refrigerated-cargo ships while berthing at six California ports: Los Angeles, Long Beach, Oakland, San Diego, San Francisco and Hueneme. The At-Berth Regulation provides vessel fleet operators visiting these ports two options to reduce at-berth emissions from auxiliary engines:


  1. turn off auxiliary engines and connect the vessel to some other source of power, most likely grid-based shore power; or
  2. use alternative control technique(s) that achieve equivalent emission reductions.


Beginning 1 January 2014, at least 50% of a fleet’s visits to a port must plug in to onshore power and total onboard auxiliary engine power generation must be reduced by at least 50%, measured against the fleets’ baseline figure. The requirement increases to 70% in 2018 and 80% in 2020.    


Further reading

Environmental legislation

LNG is a proven technology for complying with the upcoming MARPOL Annex VI regulations. At the moment, LNG is the only available option that is able to meet both the SECA and NECA requirements without the need for using marine gas oil.