Medical conditions that disqualify a commercial driver under 49 CFR 391.41
The physical qualification standards every interstate commercial driver (truck or bus, CDL or not) must meet under 49 CFR 391.41(b), one record per numbered clause: diabetes treated with insulin, high blood pressure, epilepsy, respiratory dysfunction, cardiovascular disease, vision (20/40 acuity, 70-degree field, colour recognition), hearing (whispered voice at 5 feet or 40 dB average loss), and the rest of the thirteen. Answers 'can a diabetic driver get a CDL', 'what blood pressure disqualifies a truck driver', 'CDL hearing requirement', 'CDL vision requirement 20/40'. The regulation is short and stable, but its numbered clauses set exact numeric thresholds (decibels, Snellen ratios, degrees of visual field) that generalist summaries routinely round off or drop the exception clause from -- e.g. the insulin clause is not an absolute bar, it defers to the exemption program at 391.46, and a summary that omits that turns a conditional disqualification into an absolute one.
The data
| Disqualifying condition or standard | Standard, as the regulation states it | Paragraph | Regulation section |
|---|---|---|---|
| Alcoholism | (13) Has no current clinical diagnosis of alcoholism. | (b)(13) | 49 CFR 391.41 |
| Cardiovascular disease | (4) Has no current clinical diagnosis of myocardial infarction, angina pectoris, coronary insufficiency, thrombosis, or any other cardiovascular disease of a variety known to be accompanied by syncope, dyspnea, collapse, or congestive cardiac failure; | (b)(4) | 49 CFR 391.41 |
| Colour vision (recognition of traffic signal colours) | the ability to recognize the colors of traffic signals and devices showing standard red, green, and amber | (b)(10)(i) | 49 CFR 391.41 |
| Diabetes mellitus currently treated with insulin | (3) Has no established medical history or clinical diagnosis of diabetes mellitus currently treated with insulin for control, unless the person meets the requirements in § 391.46 ; | (b)(3) | 49 CFR 391.41 |
| Distant visual acuity | (10) (i) Has distant visual acuity of at least 20/40 (Snellen) in each eye without corrective lenses or visual acuity separately corrected to 20/40 (Snellen) or better with corrective lenses, distant binocular acuity of at least 20/40 (Snellen) in both eyes with or without corrective lenses | (b)(10)(i) | 49 CFR 391.41 |
| Epilepsy or other condition likely to cause loss of consciousness | (8) Has no established medical history or clinical diagnosis of epilepsy or any other condition which is likely to cause loss of consciousness or any loss of ability to control a commercial motor vehicle; | (b)(8) | 49 CFR 391.41 |
| Field of vision | field of vision of at least 70° in the horizontal meridian in each eye | (b)(10)(i) | 49 CFR 391.41 |
| Hearing | (11) First perceives a forced whispered voice in the better ear at not less than 5 feet with or without the use of a hearing aid or, if tested by use of an audiometric device, does not have an average hearing loss in the better ear greater than 40 decibels at 500 Hz, 1,000 Hz, and 2,000 Hz with or without a hearing aid when the audiometric device is calibrated to American National Standard (formerly ASA Standard) Z24.5—1951; | (b)(11) | 49 CFR 391.41 |
| High blood pressure | (6) Has no current clinical diagnosis of high blood pressure likely to interfere with his/her ability to operate a commercial motor vehicle safely; | (b)(6) | 49 CFR 391.41 |
| Impairment of a hand, finger, arm, foot, or leg | (2) Has no impairment of: (i) A hand or finger which interferes with prehension or power grasping; or (ii) An arm, foot, or leg which interferes with the ability to perform normal tasks associated with operating a commercial motor vehicle; or any other significant limb defect or limitation which interferes with the ability to perform normal tasks associated with operating a commercial motor vehicle; or has been granted a skill performance evaluation certificate pursuant to § 391.49 ; | (b)(2) | 49 CFR 391.41 |
| Loss of a foot, a leg, a hand, or an arm | (1) Has no loss of a foot, a leg, a hand, or an arm, or has been granted a skill performance evaluation certificate pursuant to § 391.49 ; | (b)(1) | 49 CFR 391.41 |
| Mental, nervous, organic, or functional disease or psychiatric disorder | (9) Has no mental, nervous, organic, or functional disease or psychiatric disorder likely to interfere with his/her ability to drive a commercial motor vehicle safely; | (b)(9) | 49 CFR 391.41 |
| Respiratory dysfunction | (5) Has no established medical history or clinical diagnosis of a respiratory dysfunction likely to interfere with his/her ability to control and drive a commercial motor vehicle safely; | (b)(5) | 49 CFR 391.41 |
| Rheumatic, arthritic, orthopedic, muscular, neuromuscular, or vascular disease | (7) Has no established medical history or clinical diagnosis of rheumatic, arthritic, orthopedic, muscular, neuromuscular, or vascular disease which interferes with his/her ability to control and operate a commercial motor vehicle safely; | (b)(7) | 49 CFR 391.41 |
| Use of a non-Schedule I drug or substance in another 21 CFR part 1308 Schedule | (ii) Does not use any non-Schedule I drug or substance that is identified in the other Schedules in 21 CFR part 1308 except when the use is prescribed by a licensed medical practitioner, as defined in § 382.107 of this chapter , who is familiar with the driver's medical history and has advised the driver that the substance will not adversely affect the driver's ability to safely operate a commercial motor vehicle; and | (b)(12)(ii) | 49 CFR 391.41 |
| Use of a Schedule I drug, an amphetamine, a narcotic, or other habit-forming drug | (12) (i) Does not use any drug or substance identified in 21 CFR 1308.11 Schedule I, an amphetamine, a narcotic, or other habit-forming drug; or | (b)(12)(i) | 49 CFR 391.41 |
| Vision exemption alternative for the worse eye | (ii) Meets the requirements in § 391.44 , if the person does not satisfy, with the worse eye, either the distant visual acuity standard with corrective lenses or the field of vision standard, or both, in paragraph (b)(10)(i) of this section; | (b)(10)(ii) | 49 CFR 391.41 |
Where this came from
Every record above links the page it was taken from and quotes the sentence that states it. These are the 1 source this dataset was assembled from.
- ecfr.govhttps://www.ecfr.gov/current/title-49/subtitle-B/chapter-III/subchapter-B/part-391/subpart-E/section-391.41
Machine-readable
- data.jsonThe whole dataset — every record with its source URL and source quote.
- Open Knowledge Format bundleOne JSON object per line — every record's frontmatter and quoted span exactly as it is held here, in one fetch.
- data.csvThe same records as one flat table, for a spreadsheet or a dataframe. The last four columns are the source URL, the quoted sentence it was read from, the date we last checked it, and which columns are our reading rather than the page's words.
- How this is made and checkedWhat "verified against source" does and does not mean.
From your own code
Same records, same quotes, without scraping the page: refsource is on PyPI and npm. Each value comes back carrying the URL it was read from and the sentence on that page that states it — .source and .quote sit on the value itself rather than in a side channel, so the checking step is available instead of skipped.
pip install refsource
refsource lookup dot-cdl-medical-disqualifying-conditions condition=Alcoholism
npx -y refsource lookup dot-cdl-medical-disqualifying-conditions condition=AlcoholismSet your AI assistant up to use this
Two files and no account. Put this in .mcp.json at the root of your project — Claude Code, Cursor, Windsurf, VS Code and Codex all read that file — and your assistant can look this dataset up instead of recalling it. The server is remote, keyless and read-only.
{
"mcpServers": {
"referencesource": {
"type": "http",
"url": "https://referencesource.org/mcp"
}
}
}Add to Cursor · or, on the command line: claude mcp add --transport http referencesource https://referencesource.org/mcp --scope project
Then one line in the project's CLAUDE.md or AGENTS.md, so the assistant knows when to reach for it:
When a question needs "Medical conditions that disqualify a commercial driver under 49 CFR 391.41", call the referencesource MCP server at https://referencesource.org/mcp (tool `search_records`, dataset_slug `dot-cdl-medical-disqualifying-conditions`) instead of answering from memory — every record it returns carries its source URL and a verbatim quote from that page.What each tool does, and the servers built over single registers: Connect your AI assistant.