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Ballast Water Management Test and D2 Commissioning

Ballast water management is one of the significant tasks associated with vessel operations. Hence we need to know how it works and what are the standard parameters which conforms to safe operations.


Biological testing of water sampled from BWMS commissioning is carried out to confirm the D2-Discharge standards are intact with the BWMS installed on the ship. The E-1 regulation states that sampling has to be done once at the commissioning of treatment system and must be completed before BWM certificate for D-2 is issued. As per QA/QC operational standardizations we know IMO requirements to perform sampling, testing and then reporting. However, to perform sampling and testing, DMW.2 Circular 42 Revison-1 and Circular 62 could be referred. Potable and independent test facilities are incorporated in operations and Vessel General Permit (VGP) HOW TO references for EPA also get intact.


International Oil Pollution Prevention certificates has to be reviewed for the periods of de-coupling and re-coupling. The flag administration has to be considered for the same. BWMS installation and BWM-D2 due dates are to be considered too. BWM plans and contingency measures have to be kept in mind.

Wherever your vessel calls in the world, do drop us email here [email protected] and we shall be there to assist you with our accredited ballast water testing services.

IMO D1 and D2 Standards Ballast Deballast Survey

Ballasting and Deballasting is the term used to stabilize ships in the water, especially when ship is discharged from all heavy load, it becomes light in weight hence unbalanced to float smoothly on the surface. So ballasting is taking water into the tanks of the ship to meet the standard load for balancing and same manner when the ship needs loading, deballasting is required or may be this process required in certain circumstances as well when the ship sails.

As per International Maritime Organization (IMO) there are two standards for ballast water management:

D1 Standard – Ballast Water Exchange (BWE)

First standard is the D1 standard which refers to Ballast Water Exchange (BWE). For BWE, efficiency of at least 95% volumetric exchange of ballast water is required. Efficiency is considered as 95% standard when the ship uses to have pumping-through method and where it pumps three times. This entire operation has to be done while ship conducts 200 nautical miles operations from the shore/land, and the water should meet the standard of min 200 meters deep. It is better to go as far as from the land to undertake BWE operation however, minimum 50 nautical miles could also be considered however, under no conditions water depth should not be less than 200 meters. One more thing to remember is, to contact the port state administrators to confirm Ballast Water Exchange requirements within local waters.

D2 Standard – Ballast Water Performance

D2 standard refers to performance of the ballast water and this is all about chemistry and the laboratory testing where we need to get report for D2- Ballast Water Performance Testing from accredited lab. Purpose of D2 standard is to stipulate the level of acceptance of organism that could be found in the discharge ballast water.

  • The viable organisms fewer than 10 greater than or equal to 50 micrometers in minimum dimension per cubic meter;
  • The viable organisms fewer than 10 less than 50 micrometers in minimum dimension and greater than or equal to ten micrometers in minimum dimension per milliliter.

Additionally, a ballast water discharge of indicator microbes, as a health standard, shall not exceed the following specified concentrations:

  • Toxicogenic Vibrio cholerae (O1 and O139) with less than one colony-forming unit (cfu) per 100 milliliters or less than 1 cfu per 1 gram (wet weight) zooplankton samples;
  • Escherichia coli less than 250 cfu per 100 milliliters;
  • Intestinal Enterococci less than 100 cfu per 100 milliliters

If you require our services, please visit our page Ballasting and Deballasting Inspection Services or you require ballast water analysis, please visit our page Ballast Water Testing for all the specifications.