Some mariners pay for a drug test they did not need. Others submit a credential application without one and have it returned for missing documentation. Both mistakes can come from the same gap: 46 CFR 16.220 lists specific transactions that require a chemical test, while the National Maritime Center (NMC) separately describes several transactions that do not.
Start by identifying the exact transaction the NMC will process—not just what you call it. Then check whether you qualify for one of the regulatory exemptions before booking a test.
MMC Transactions That Require a Drug Test
Under 46 CFR 16.220(a), an applicant must pass a chemical test for dangerous drugs and submit the results when applying for:
An original Merchant Mariner Credential (MMC).
First issuance, raise of grade, or renewal of an officer endorsement.
A raise of grade of an MMC.
Your first endorsement as Able Seafarer, Lifeboat Operator, QMED, or a tank vessel endorsement.
Reissuance of an MMC with a new expiration date.
The rule separately names renewal of an officer endorsement and reissuance of an MMC with a new expiration date. Do not assume every transaction you might casually call a “renewal” or “replacement” has the same classification. Check how the NMC has categorized your application.
When a new test is required under paragraph (a), its result must be dated no more than 185 days before your application is submitted. The clock is measured from your submission date—not from when the NMC processes the application.
Transactions the NMC Says Do Not Require a Test
The NMC's drug-testing guidance says a test is required for all transactions except Documents of Continuity modifications (increases of scope), duplicates, and International Endorsements (STCW).
These exceptions are described in NMC administrative guidance; they are not a separate list of exceptions printed in § 16.220(a). The regulation itself still controls which transactions trigger the requirement, including raises of grade. If your transaction sits near that line—or combines multiple transaction types—confirm its classification with the NMC before deciding to skip a test.
Duplicate credential
The NMC lists duplicate transactions among those that do not require a drug test. If you are replacing a lost or damaged credential, confirm that the application is being processed as a duplicate.
Standalone International Endorsement (STCW)
The NMC's drug-testing page identifies International Endorsements (STCW) as an exception. This refers to the STCW transaction itself; it does not remove a test requirement that applies to another transaction in the same application.
Document of Continuity modification (increase of scope)
The NMC identifies Documents of Continuity modifications (increases of scope) as an exception. Because 46 CFR 16.220 separately requires testing for certain raises of grade, confirm the transaction classification with the NMC when the distinction is not clear.
A separate option: Document of Continuity
Under 46 CFR 10.227(g), a holder of national endorsements who cannot meet the renewal requirements in paragraph (d) may be able to apply for a Document of Continuity. The rule says these documents do not expire, but they do not entitle the holder to serve as a merchant mariner. This preserves a route to renew later; it is not a way to continue working on an expired credential. STCW endorsements cannot be placed in continuity, and placing the related national endorsements in continuity invalidates them. The rule also limits conversion for credentials beyond the applicable 12-month grace period. Review paragraphs (g) and (h) and confirm your circumstances with the NMC.
Two Ways You May Not Need to Submit a New Test
Even when your transaction normally requires testing, 46 CFR 16.220(c) says you do not have to submit evidence of a new test if you can document either of the following:
1. A recent passing test
You passed a required chemical test within the previous six months, with no subsequent positive chemical test during the remainder of that period.
2. Qualifying random-program participation
You were subject to a random testing program meeting 46 CFR 16.230 for at least 60 days during the previous 185 days, and you did not fail or refuse a required test during that period.
These are three different timelines: 185 days before application for a new test; six months for a previously passed test; and at least 60 days of qualifying program participation inside the previous 185 days. Do not treat them as interchangeable.
Participation alone is not the whole requirement—you must be able to show it. The NMC lists a letter attesting to random-program participation among accepted documentation options, alongside an approved test result and a letter attesting to pre-employment testing. Confirm the NMC's current content and submission requirements; do not assume a generic membership confirmation will be enough.
If one application covers multiple transactions, 46 CFR 16.220(d) generally requires only one passing result, subject to the pilot exception in paragraph (b). Pilots required to hold an annual physical are addressed separately under § 16.220(b); results submitted within 12 months of the application date do not need to be resubmitted under paragraph (a).
Join APCA's USCG Random Testing Consortium
Get compliant random-pool participation, ongoing program administration, and records that can support an MMC application once you meet the 60-days-within-185-days eligibility rule. Enrollment today does not replace that required participation window.
Already an APCA member? Contact us for participation documentation.
Document the Test So Your Application Is Complete
If you need a new test, it must follow DOT procedures under 49 CFR Part 40. The specimen must be sent to a SAMHSA-accredited laboratory for analysis. The NMC's optional CG-719P form describes the options for documenting your test or exemption; for the passing-test option, the result must be signed and dated by a Medical Review Officer (MRO).
The NMC identifies several ways to document testing, including Copy 2 of the federal Custody and Control Form signed by the MRO, a completed CG-719P, or an MRO-signed letter from the facility. For random-program participation, use documentation that establishes your qualifying participation and follow the NMC's latest instructions.
Credential submissions are now handled through the Coast Guard's NAVITA system. Check the current NMC drug-testing guidance and NAVITA portal before submitting; do not rely on older paper-submission instructions without confirming they still apply.
Need a one-time test—or a continuing random program?
The right option depends on your MMC transaction and whether you work in a covered commercial-vessel role. A one-time test does not replace required random testing for covered crewmembers.
The Bottom Line
Before you book a test, identify your exact transaction. Per NMC guidance, duplicates, standalone STCW International Endorsements, and Documents of Continuity modifications (increases of scope) generally do not require one—but confirm the classification if there is any doubt, especially when your application includes a raise of grade.
If your transaction does require testing, check both exemptions in § 16.220(c). A passing test within the previous six months or at least 60 qualifying days in a compliant random pool within the previous 185 days may mean you do not need to submit a new test. Keep documentation ready, and use the NMC's current NAVITA instructions when submitting.
Frequently Asked Questions
I'm replacing a lost MMC. Do I need a drug test?
The NMC lists duplicate transactions among those that do not require a test. Confirm that the NMC has classified your application as a duplicate; the transaction type on the application matters more than the informal name you use for it.
How recent must a new drug test be?
Under 46 CFR 16.220(a), the test must be dated no more than 185 days before the date you submit your application. The separate exemptions in 16.220(c) use a six-month window for a prior passing test and a 60-days-within-185-days test-program participation window.
If I'm enrolled in a consortium, do I still need a new test?
Possibly not. Under 46 CFR 16.220(c)(2), you may not need to submit evidence of a new test if you were subject to a compliant 16.230 random testing program for at least 60 days during the previous 185 days and did not fail or refuse a required test. You must be able to document qualifying participation; confirm the NMC's current letter requirements.
Can one test cover multiple MMC transactions?
Generally, yes. Under 46 CFR 16.220(d), one passing result is required when a single application covers multiple transactions, subject to the pilot provision in paragraph (b).
Does a Document of Continuity let me keep working without testing?
No. A Document of Continuity can preserve eligibility to renew later for eligible national endorsements, but it does not entitle its holder to serve as a merchant mariner. It defers the renewal requirements; it is not a substitute for a valid credential to work.
Can I use a one-time test if I work on a commercial vessel?
A one-time test may address an MMC application requirement, but it does not replace the random testing program required for covered commercial vessel service. If you work as a covered crewmember, ask about the USCG consortium requirements that apply to your role.
Sources
- 46 CFR 16.220 — Periodic testing requirements
- 46 CFR 16.230 — Random testing requirements
- 46 CFR 10.227 — Requirements for renewal and Documents of Continuity
- U.S. Coast Guard National Maritime Center — Drug Testing
- CG-719P — DOT/USCG Periodic Drug Testing Form
- 49 CFR Part 40 — DOT testing procedures
- NMC NAVITA Frequently Asked Questions