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Merchant Mariner Credential (MMC) Renewal


Under maritime law, a maritime license like a Merchant Mariner Credential (MMC) is required for certain mariners working aboard merchant vessels. The MMC is required for employees aboard a U.S. merchant vessel in excess of 100 gross register tons. Operators on uninspected passenger vessels are not required to have the MMC.

Seamen may obtain additional ratings that may allow them to work in more advanced positions – this may require a certain amount of experience. In addition to proper credentials to ensure a worker is qualified, maritime training requirements may also be necessary before a seaman can work aboard a ship.

When to Renew a Maritime License

MMCs are good for five years and can be renewed at any time before the five-year period is up. After this period, there is a grace period of one year. It is important to not wait until the last minute. If a worker fails to renew within the five year period or the grace period, he/she may have to retake the exams to get the license.

So seamen are not put in a situation in which their employment is in jeopardy because an MMC has expired, they are generally advised to start the renewal process several months prior to expiration.

Requirements to Renew an MMC

A seaman generally must have a valid Transportation Worker Identification Credential (TWIC) first before renewing the MMC. The TWIC allows seamen access to secure areas on vessels.

Mariners hoping to renew an MMC must also pass a medical exam. Workers must pass a physical exam and their doctor must fill out the appropriate forms. Further, mariners with 360 days or more experience over the last five years may be able to renew without taking an exam or course; those without proper experience may need to meet this requirement to renew the maritime license under maritime law.



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