What 391.21 means in plain language
FMCSR 391.21 requires that every driver employed by a motor carrier must complete and submit a formal application for employment before beginning work. This is a foundational hiring requirement—it's not optional, and it's not something that happens after you start driving.
The regulation ensures that carriers have documented proof of your employment authorization, background information, and eligibility to operate a commercial vehicle. The application creates a paper (or digital) trail that connects you to your employer and gives the carrier the information it needs to verify your qualifications before you touch a steering wheel.
When an inspector cites 391.21, they have typically discovered that a driver was operating a commercial motor vehicle without a completed employment application on file. This might mean the application was never submitted, was submitted late, or was missing from the carrier's records during the inspection.
What our enforcement data actually shows
Across our 13 million+ inspection records, 391.21 has never resulted in a citation. The all-time citation count is 0, with 0 citations in the last 12 months and 0 in the last 90 days. Because there are no recorded violations of this code in our database, the out-of-service rate is 0.0%.
This extremely low enforcement volume is notable: it suggests that either carriers and drivers are universally compliant with employment application requirements, or inspectors rarely uncover violations of this specific code during roadside checks. The absence of data makes it difficult to predict enforcement patterns or severity outcomes.
If you have been cited for 391.21, you are in a rare situation. The citation carries a CSA Severity Weight of 2, which is relatively low on the severity scale, and it does not make you eligible for out-of-service placement at roadside.
Who gets cited most
Because our inspection records contain zero citations for 391.21, we cannot identify which states or carriers are most frequently cited for this violation. There is no state-level or carrier-level breakdown to analyze.
If you are facing a citation for this code, your best step is to work with your carrier's safety and compliance department to immediately resolve the employment application issue and provide documentation to the enforcement agency.
How severe is this compared to similar codes
Other codes in the Driver Fitness category show dramatically different enforcement profiles. For example:
- 383.23(a)(2) (CDL – wrong class) has 50,385 all-time citations with a 98.4% out-of-service rate, indicating this is one of the most frequently cited and most serious driver qualification violations.
- 391.41(a) (Physical qualification – general) has 42,270 citations with a 16.2% out-of-service rate, showing that physical qualification issues are common but less likely to result in immediate removal from service.
- 391.41APC (Medical Certificate) has 49,539 citations with a 97.1% out-of-service rate, making medical certificate violations nearly certain to trigger out-of-service placement.
By comparison, 391.21's zero citations suggest it is either exceedingly rare or handled through different enforcement pathways (such as carrier audits) rather than roadside inspections. Its non-OOS-eligible status also means it will not remove you from service on the spot, even if cited.
How to avoid it
Since 391.21 addresses employment documentation that should be completed before you are hired, the primary responsibility falls on your carrier. However, as a driver, you can take these steps:
- Complete all employment paperwork before your first shift. Do not assume verbal hiring arrangements satisfy FMCSR requirements. Insist on completing a written employment application and confirm it has been submitted to your carrier's compliance office.
- Keep a personal copy of your signed employment application. This is your proof of compliance if a question ever arises during an inspection.
- Verify with your carrier's safety department that your application is on file. Before you start driving, ask to see confirmation that your employment application has been properly logged in the carrier's hiring and compliance records.
- Review your carrier's employment process. If you notice that your carrier is not using a formal application for employment, report this to your carrier's compliance officer or safety manager. Operating without proper documentation creates liability for the entire fleet.
- If you change carriers, repeat the process immediately. Each new employer must have a completed application for employment on file before you operate under their authority.
Your carrier is required by law to maintain employment applications as part of the driver file. As a driver, your job is to ensure you complete your side of that requirement on day one and keep documentation that you did so.