The short version
- 46 CFR part 109, the MODU operating rules, contains no first aid, medicine chest or medical care section.
- The one medical requirement in Subchapter I-A is 46 CFR 108.209, hospital spaces, and it sits in the construction part rather than the operating part.
- 108.209 counts persons, not crew, so on a drilling unit the industrial complement is inside the headcount.
- 46 CFR 109.103 brings SOLAS in only for a self-propelled unit over 500 gross tons on an international voyage. Most domestic units meet none of those.
- Casualty reporting and logbook duties still apply through 109.411 and 109.433.
Dutch, Korean, Greek and Palauan sources answering a United States question
A live capture of the first page for this question in August 2026 returned a Dutch government copy of the 1989 MODU Code, the Korean Register of Shipping, a Greek classification society, a Federal Register notice about electrical equipment, an IMO rules aggregator, a class society guidance PDF, the Palau ship registry, Coast Guard MODU regulatory guidance and a training company page. The generated summary above them cited a document sharing site and opened with personal medical fitness standards.
Every one of those instruments is real. Most of them are irrelevant to a jack-up working a Gulf of Mexico block under United States flag, and the one United States source on the page does not address medical matters at all.
Two questions the answers merge into one
Before any regulation is useful, the question has to be split, because the search results treat two unrelated subjects as a single topic.
| Question | What it is really about | Where the answer lives |
|---|---|---|
| Are the people fit? | Personnel medical fitness. A credentialing and employment matter, and the subject the search results lead with | Not in Subchapter I-A. Not addressed in this article |
| What must the unit provide? | Facilities and equipment carried by the unit itself, and what happens when someone is hurt on it | 46 CFR 108.209 and 108.210 for the facility[3][4], and 46 CFR part 4 for the aftermath[9] |
An operator who has satisfied a fitness standard has done nothing whatsoever about the second question, and it is the second question a Coast Guard inspector asks on the unit.
The one facility rule, and it is not where you would look
Subchapter I-A does contain a medical requirement, and it is easy to miss because it sits in the construction part rather than the operating part. 46 CFR 108.209 requires a hospital space on each unit carrying twelve or more persons on a voyage of more than three days[3], and it runs to ten lettered paragraphs of specification. 108.210 removes the requirement where a designated treatment or isolation room meets three stated conditions[4].
The word that decides your headcount
108.209 counts persons, not crew. On a drilling unit the industrial complement is usually several times the marine crew, so a rule that looks like it applies to large vessels applies to almost every working unit. The berth formula then excludes anyone berthed in a single occupancy room, which pulls the number back down again. Getting those two steps in the right order is the whole calculation.
The full specification, the berth formula and the exception are set out in the hospital space article rather than repeated here, because the same two rules govern cargo vessels as well and the comparison is where the useful detail sits.
The operating rules contain nothing medical
Part 109 is where an operator would reasonably look, and it is where the absence is. Its seven populated subparts cover general provisions and the operating manual, tests and drills, operation and stowage of safety equipment, reports and notifications and records, emergency signals, cranes, and a miscellaneous subpart running from propulsion boilers to helicopter fueling[1]. Subpart B alone covers steering gear, sanitation, boilers and machinery, watertight integrity appliances, emergency lighting, drills and firefighting equipment[1], which is a thorough treatment of everything except the people. There is no first aid section, no medicine chest section and no medical care provider role anywhere in it.
What part 109 does carry are the duties that surround a medical event rather than the capability to handle one.
| Section | What it obliges | What it does not do |
|---|---|---|
| 109.213 Emergency training and drills |
Drills and emergency training on the unit[6] | Medical response is not among the named subjects, so a unit can drill in full compliance and never rehearse an injury |
| 109.411 Notice and reporting of casualty |
Casualty notice and reporting, routing to 46 CFR part 4 in the ordinary way[7][9] | It sets no threshold of its own. That test lives in part 4 and turns on the treatment given, examined in the beyond first aid article |
| 109.433 Logbook entries |
Where an Official Logbook is carried, the statutory items in 46 USC 11301 apply, including each illness or injury and the medical treatment given[8][10] | The medical entries arrive through the statute rather than through Subchapter I-A, which is why reading part 109 alone misses them. See crew medical records |
Read the third row against the first. A MODU can hold every drill part 109 names, log everything 109.433 lists, and still have no written standard for what is in the medical locker or who decides when someone leaves the unit. That decision framework is in the evacuation article.
The SOLAS route is narrower than the search results suggest
Most of the page one material assumes an international regime, so it is worth reading the section that actually brings SOLAS into Subchapter I-A.
46 CFR 109.103
“No self-propelled unit of more than 500 gross tons may embark on an international voyage unless it is issued the appropriate Convention certificate as described in §§ 107.401 through 107.413 of this subchapter.”[2]
Three conditions, all of which must hold. Self-propelled. More than 500 gross tons. Embarking on an international voyage. A jack-up under tow, a moored semi-submersible, or any unit working a domestic block satisfies at most one of them[2]. For those units the Convention certificate is not required, and the international medical provisions that flow from that certificate do not reach them either.
That does not make the international material worthless. A classed unit still answers to its society, a foreign flagged unit answers to its flag, and a charterer can impose whatever it likes. It does mean that quoting the MODU Code at a domestic Gulf unit describes a standard the operator has chosen or inherited, not one the CFR imposes.
What to write down
- Run the 108.209 headcount and record the result. Persons, then the single occupancy exclusion[3]. One line, and it decides whether you owe a compartment.
- Decide between the hospital space and the 108.210 designated room, in writing. The exception has three physical conditions and one paperwork condition[4], and the method is in the hospital space article.
- State plainly which international instruments apply and why. Class, flag or charter, named individually. Anything not on that list is not your standard.
- Set the medical contents standard yourself. Part 109 gives none, so borrow a published one and say which. The three United States kit rules are compared in the vessel class comparison, and offshore supply vessels face the identical problem in the Subchapter L article, where the only kit named sits inside the rescue boat[11].
- Assign the reporting and logbook duties to named people ashore, because 109.411 and 109.433 are the parts that bite after an incident[7][8], and the audit view is a compliance audit inside the wider structure of the six decisions.
Step three is the one that changes conversations with charterers, because it replaces an argument about which code applies with a document. If you want that separation done and the medical standard set behind it, that is maritime medical consulting and chest management. Everything else is indexed in the guidance library, and the physician who reviews it is on the about page.
Common questions
Does a US MODU have a medical requirement in the CFR?
One, and it is a facility rather than equipment. 46 CFR 108.209 requires a hospital space on a unit carrying twelve or more persons on a voyage of more than three days, with 108.210 providing an exception. The detail is set out in the hospital space article. Part 109, the operating rules, contains no medical section at all.
Is there a first aid kit requirement for a MODU?
Not in Subchapter I-A. Part 109 has seven subparts covering tests and drills, safety equipment operation, reports and records, emergency signals, cranes and miscellaneous, and none of them is medical. That leaves the contents standard to the operator, the same position offshore supply vessels are in, described in the Subchapter L article.
Does SOLAS apply to our unit?
Probably not, and this is the assumption worth testing. 46 CFR 109.103 conditions the Convention certificate on a unit being self-propelled, more than 500 gross tons, and embarking on an international voyage. A jack-up or a moored semi-submersible working a Gulf of Mexico block meets none of those, so the international regime the search results describe does not reach it.
Why do search results answer this with the MODU Code and class society rules?
Because those are what rank. A live capture in August 2026 returned a Dutch government copy of the 1989 MODU Code, the Korean Register, a Greek class society, an IMO rules aggregator, a class society guidance PDF and the Palau ship registry. Those instruments matter to a unit that is classed or foreign flagged. They are not the United States regulatory answer for a domestic unit.
What happens after an injury on a MODU?
46 CFR 109.411 carries the casualty notice and reporting duty, which routes to 46 CFR part 4 like every other commercial vessel. The threshold that decides whether an injury is reportable is a two part test explained in the beyond first aid article, and the sequence after a death is in the death on board procedure.
Do we have to log an illness or injury?
46 CFR 109.433 governs logbook entries, and where an Official Logbook is carried the items required by 46 USC 11301 apply, which include each illness or injury and the medical treatment given and each death on board. The wider records position, including the crewmember access question, is in crew medical records.
Are crew medical fitness standards part of this?
They are a different question and the search results merge the two. Personnel medical fitness is a credentialing and employment matter. What this article covers is what the unit itself must provide. Keeping them apart is the first step, because an operator who has satisfied a fitness standard has done nothing at all about the facility requirement in 108.209.
