The U.S. Coast Guard has announced an updated interpretation regarding sea service credit that will significantly impact mariners working on articulated tug barges (ATBs) and integrated tug barges (ITBs). This revision represents a positive step forward, aimed at supporting mariner career progression and streamlining regulations for those holding unlimited tonnage endorsements.
Effective immediately, mariners who already hold an unlimited tonnage officer endorsement and are seeking a higher-grade unlimited endorsement (such as 3rd Mate to 2nd Mate, 2nd Mate to Chief Mate, or Chief Mate to Master) will now receive day-for-day credit for sea time.
This credit applies specifically when their sea time is served on ATBs and ITBs that meet two conditions: they operate exclusively as a composite unit and they possess an aggregate tonnage above 1,600 gross register tons (GRT).
This updated interpretation acknowledges that when an ATB or ITB operates as a single, composite unit, the experience gained by mariners is equivalent to that on other large, single-hull vessels.
Documenting Your Sea Service for Credit
To properly claim this day-for-day credit, it is essential that your service is accurately documented on your Sea Service Letter. Mariners should ensure the following is clearly stated by the operating company: the letter must clearly state that the ATB or ITB operated exclusively as a composite unit during the specified service period and the aggregate GRT tonnage (for both the tug and barge) should be written next to each sea service entry for mariners with unlimited officer endorsements.
It is recommended that the following statement be included below the sea service entries depending on if it’s an ATB or ITB: "(Vessel name) is an ATB that operates exclusively as a composite unit," or "(Vessel name) is an ITB that operates exclusively as a composite unit."
Mariners with pending applications or those who have received "Awaiting Information" letters that this new credit may affect should be proactive and provide an updated sea service letter that clearly states the vessel operates exclusively as a composite unit.
Looking Ahead: Industry Calls for Broader Application
While this interpretation adjustment is a welcome development that will help make sailing on ATBs more attractive to unlimited officers again, it also highlights existing limitations. The barriers to mariner career progression under 46 CFR 11.211(d) are still in place for mariners who do not hold an unlimited deck officer endorsement and are working to advance their careers on ATBs that operate exclusively as a composite unit.
The logic underpinning this positive change – recognizing the functional equivalence of a composite ATB/ITB to a single vessel – establishes a strong foundation. Industry is hopeful that the Office of Merchant Mariner Credentialing will take this opportunity to further recognize the value of all mariners working on ATBs that operate exclusively as a composite unit. Industry advocates for refining the language to include all ATBs and ITBs operating exclusively as a composite unit, regardless of specific tonnage thresholds or the mariner's current license level, for day-for-day credit.
Such a comprehensive interpretation would further simplify credentialing and provide clear pathways for mariners to reach the wheelhouse while pursuing a career aboard our nation's ATB fleet. This would continue to support the Coast Guard's stated goals by facilitating career progression for an even wider range of skilled mariners throughout the industry.
The Coast Guard's proactive step in this area is a testament to its responsiveness to industry needs, and the maritime community anticipates future developments that will enhance the efficiency of the merchant mariner credentialing system.
