Regional Issues
Air Pollution from Marine Shipping - International, National, and State Initiatives
Page last updated July 14, 2008.

Regulatory Strategies

International Action

In 1973, an international conference of the IMO adopted the International Convention for the Prevention of Marine Pollution from Ships (MARPOL), and an accompanying treaty (these treaties are termed "Annexes") designed to prevent pollution from ships.

In 1997, the IMO agreed to MARPOL Annex VI, a global treaty to reduce air emissions from ships. The treaty will become effective one year after it's been ratified by at least fifteen nations, representing a minimum of fifty percent of the world's shipping tonnage. The treaty has not yet met both requirements.

On May 18, 2004, MARPOL Annex VI was ratified by the fifteenth nation, bringing the total percent of the world's merchant shipping tonnage to 54.57%. Annex VI went into effect on May 19, 2005.  The U.S. was not among the fifteen nations that ratified the treaty.

As of March 2007, 41 countries - not including the U.S., Canada, and Mexico - have ratified the treaty.

MARPOL Annex VI:

• Sets limits on sulfur dioxide (SOx) and NOx emissions from ships, and prohibit the intentional emission of ozone-depleting substances such as chlorofluorocarbons.

• Sets a global limit on the maximum allowable sulfur content of fuel oil used in shipping to 4.5% m/m, and call for the IMO to monitor the worldwide average sulfur content of shipping fuel.

• Establishes specific "SOx Emission Control Areas" with more stringent controls on SOx emissions (1.5% m/m).

• Prohibits on-board incineration for ships carrying certain products.

U.S. Action

On July 8, 2008, The U.S. House of Representatives approved H.R. 802, legislation that directs the U.S. Environmental Agency to place limits on emissions from large ships. The bill, which now awaits signature by the President, would bring the U.S. into agreement with the MARPOL Annex VI treaty. For the text of the bill, see the House of Representatives' website and search by H.R. 802.

On April 23, 2007 the USEPA Administrator signed a rule shifting the deadline for USEPA rulemaking on large ship engines from April 27, 2007 to December 2009.  APCD has sent a letter to USEPA expressing concern about this new delay in the rulemaking schedule. The California Air Pollution Control Officers Association has also sent USEPA a letter expressing concerns about the delay. Download these letters here.

In 2003, the USEPA released a draft rule addressing large ship engines. APCD submitted comments on the draft rule, recommending that USEPA:   

• Set stringent new standards for NOx emissions from marine engines that will encourage technology advancement in this area.
   
• Apply new standards to both U.S. and foreign flagged ships.
   
• Identify and encourage incentive programs to reduce air emissions from the existing fleet.
   
• Set fuel sulfur limit requirements for both U.S. and foreign-flagged ships.
   
• Actively pursue international agreements to take advantage of a crucial opportunity to set the stage for international emission-reduction efforts.
   
• Keep in mind that reducing emissions from these marine vessels is more cost-effective than pursuing additional reductions from onshore industry, and that setting stringent standards for new engines now is more cost-effective than retrofitting those engines years from now.

See this page to download comment letters by APCD and other agencies and organizations.

State Action

On December 8, 2005 the California Air Resources Board (CARB) approved a regulation to reduce emissions from auxiliary diesel engines and diesel-electric engines operated on ocean-going vessels within California waters and 24 nautical miles of the California coastline. The regulation applies to both US and foreign flagged ships visiting CA ports, and requires them to use a cleaner fuel in their auxiliary engines while in the regulated region.

An injunction in federal court prevented CARB from implementing this regulation. CARB has since rewritten the regulation to potentially avoid the legal barriers identified by the court, and this is in process.

Santa Barbara Channel photo courtesy of Lennart Lövstrand

APCD Contacts