The U.S. Coast Guard (USCG) has published an interim rule to update and revise regulatory tables at 46 CFR Subchapter O (Parts 150 to 155), which list liquid hazardous materials, liquefied gases, and compressed gases that have been approved for maritime transportation in bulk and that indicate how each substance’s pollution potential has been categorized.

The interim rule revises the pollution prevention categories assigned to each substance to align with those used by the International Maritime Organization’s Marine Environment Protection Committee (MEPC).  The updated information is of value to shippers and the owners and operators of U.S.-flag tank and bulk cargo vessels in any waters and most foreign-flag tank and oceangoing bulk cargo vessels in U.S. waters. 

According to the USCG, the rule includes no new decisions about whether any specific chemical substance should be approved for bulk maritime transportation, about how any specific substance should be categorized, or about carriage requirements that should apply to any specific substance. 

Three-part agreement

Subchapter O lists hundreds of hazardous liquids, liquefied gases, and compressed gases that the USCG has approved for bulk transportation; the subchapter also specifies requirements for safely transporting these substances.  If a substance is not already listed in the subchapter, a vessel owner or operator must request the USCG’s written permission to transport the substance. 

Also, if the substance is to be shipped internationally, the owner or operator must conclude an agreement with the USCG and the flag administration of the country to which the substance will be shipped.  The agreement categorizes the substance’s potential for pollution and sets its minimum safe carriage requirements in accordance with the International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk (IBC Code).  The code contains international standards for the safe maritime bulk transportation of dangerous and noxious liquid chemicals in accordance with the International Convention for the Prevention of Pollution from Ships (MARPOL).  

The agreement is forwarded to the MEPC, which reviews the information and either approves or modifies it.  Each December, the MEPC releases a circular identifying the new substances for which it has completed review.  The circular lists the countries that have approved international maritime transportation of the substance and provides information about each substance’s pollution categorization and minimum transportation safety requirements. 

2007 categorization

In 2007, the MEPC changed hazardous substances categorization from an A-B-C-D scheme (with A representing the most severe pollution hazard) to an X-Y-Z-OS scheme (with X,Y, and Z representing decreasing hazard levels and OS representing other substances that present no significant pollution hazards). 

The USCG notes that its current Subchapter O still uses the outmoded A-B-C-D pollution categories and does not convey information under the X-Y-Z-OS categories.  According to the USCG, the update provides the regulated community with more current information, thereby achieving a “modest reduction” in regulatory burden.

“Our plan is to keep the table updated through annual rulemakings in the future,” says the USCG.

The interim rule was published in the August 16, 2013, FR.