US Coast Guard denies MPN appeals

Examples of organisms transported in ballast water (image courtesy of GEA) Examples of organisms transported in ballast water (image courtesy of GEA)

UPDATED WITH REACTION. The US Coast Guard (USCG) has denied appeals to allow the ‘most probable number’ method of sampling in type approval testing for ballast water management systems.

The manufacturers appealed following the US decision in December that the MPN method was not equivalent to the required CMFDA/FDA (vital stain) method. The appeals were denied on the grounds that USCG “lacked the discretion to approve a testing alternative that would change the discharge standard”.

Suppliers were also unable to show that their systems met the regulatory requirements for approval of an alternative test, USCG said.

In a statement USCG noted: “MPN was developed to estimate numbers of cells of a single species with well-known culturing (or growth) requirements. With regards to evaluating ballast water that has thousands of different kinds of species, MPN-based methods have not been validated to date for this purpose.”

Rasmus Folsø, CEO of DESMI Ocean Guard, one of the four suppliers whose appeals were denied, reacted by reporting that it will now begin testing based on the FDA method. “These tests have been planned and prepared during the spring and are now ongoing at DHI test facility in Denmark," he said. "We expect to finalise the land based testing this fall aiming for USCG type approval of the RayClean system in late 2016.”

Meanwhile, the USCG indicated that MPN could be allowed in fututre, depending on a review underway by the US Environmental Protection Agency’s Environmental Technology Verification (ETV) technical panel. A new version of the ETV protocol would need to be incorporated by reference into the USCG’s regulations – with a new rulemaking including public notice and comment process.

The USCG added: “There are several UV-based BWMS going through type approval testing right now under the required test procedures. This denial does not adversely affect the 20 BWMS manufacturers currently using testing standards published in Coast Guard regulations.

“This denial also has no immediate impact on shipping. These UV systems are still accepted for use by the Coast Guard as Alternate Management Systems (AMS). US regulations allow ships to use AMS for five years from their compliance date. Ship owners and operators can also still continue to apply for, and receive, extensions to their compliance dates.”


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