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Filter performance testing

Requirements for filter testing

We offer testing of filtration units for use in ballast water management systems (BWMS) in accordance with the IMO and U.S. Coast Guard requirements for type approval. The U.S. Coast Guard defines two standard procedures for testing to include an upgraded filter version or a new filter in the existing type approval certificate.

Upgraded filter testing is the less comprehensive testing procedure, which includes two tests of an upgraded filter version in each of two test water salinities. The testing procedure is designed to verify equivalence between filters.

The tests are typically performed as comparison testing between the old and a new version of the filter. The filter comparison test normally includes analyses of water quality parameters and live organisms ≥50 µm. The ‘upgraded filter testing’ is required, when the filter manufacturer makes significant changes of the filter, such as mesh geometry, additional backwash suction-arm or a new and more compact design.

Upgraded filter testing

Alternate filter testing

Alternate filter testing is the more comprehensive testing procedure, which includes three tests of a new filter in each of three test water salinities.

The new filter will be connected to the BWMS, and the testing will be performed according to the requirements for type approval of BWMS.

BWMS manufacturers are welcome to contact us directly for an initial discussion of the challenge conditions and the design of the filter performance testing. If you have not selected an independent laboratory (classification society) to overview the testing, we may introduce you to the parties with whom we collaborate, i.e., DNV GL, Lloyd’s Register and Prüfinstitut für Abwassertechnik (PIA).

How does it work?

Key Features

Equivalence between filters can be determined by applying statistical tools of the results from filter testing.

Testing can be completed in 1 month (upgraded) or 2 months (alternate) from the date of installation.

Testing can be performed at our test facility in Denmark or at the manufacturer’s own facilities.



Do you wish to expand your type-approval certificate to include a new or upgraded filter?

Consult with DHI’s expert for more information:

Gitte I. Petersen: