In addition to setting standards for the safe transport of explosives, compressed gases, acute poisons, various fire hazards, and biological and radioactive hazards, the US DOT’s Hazardous Materials Regulations also protect the long-term health of the public and the environment by regulating various substances that are hazardous to the air, water, and land. One of the primary categories of environmental hazardous substances are marine pollutants—substances that are toxic to aquatic life.
US vs. International Criteria for Marine Pollutants
The US DOT defines marine pollutants as materials that contain an elevated concentration of one or more of the chemicals listed in 49 CFR 172.101, Appendix B. For most materials the marine pollutant threshold is a 10% concentration of Appendix B chemicals. Others, known as “severe marine pollutants” (designated by the letters “PP” in Appendix B), are regulated at a 1% concentration.
The international authorities use a different set of criteria for marine pollutants. As codified by the International Maritime Organization in its Dangerous Goods Code, also known as the IMDG Code, a substance is a marine pollutant if it is toxic to the aquatic environment when evaluated by the test methods given in Chapter 2.9.3 of the IMDG Code.
Known and suspected marine pollutants are indicated by the symbol “P” in Column 4 of the Dangerous Goods List in Chapter 3.2 of the IMDG Code or in the MP column of the Code Index. When a substance’s effect on the aquatic environment is unknown, or when you are offering a mixture or solution that contains a designated marine pollutant, you must evaluate the material according to IMDG 2.9.3.
Shipping Marine Pollutants
When transported by vessel, marine pollutants are shipped in much the same way as other hazardous materials. Some additional rules apply, such as extra descriptions on shipping papers and marking requirements for packages. [49 CFR 172.203(l) and 172.322] Also, if a marine pollutant meets the criteria of Hazard Classes 1 through 8, it should be assigned to the appropriate hazard class. If not, then the material should be assigned to Class 9 Packing Group III unless there is a specific entry in Class 9 for the substance. When shipped by ground or air in the United States, marine pollutants require additional communications only when shipped in bulk packages. [49 CFR 171.4]
It is very important to understand the differences in classification in order to properly regulate a material that could pose a danger to an aquatic environment, while at the same time avoiding over-classification.
Ensure compliance with the International Maritime Organization’s rules for shipping hazmat by vessel at the Hazmat Vessel Shipper Certification (IMDG) Webinar! Mandatory compliance with the IMDG Code, Amendment 36-12, begins on January 1, 2014. Don’t be caught off guard when the new rules go into effect.