What 397.3AU means in plain language
397.3AU falls under the hazardous materials transportation rules. This code addresses specific requirements for how hazmat shipments must be prepared, documented, or handled before they leave a facility or during transport. The exact violation typically involves a deficiency in the procedures, documentation, or physical state of a hazardous material shipment that fails to meet Department of Transportation standards.
If you received this citation, an inspector found that something about the way your hazmat load was prepared, packaged, labeled, or documented did not align with federal hazmat transportation requirements. This is distinct from violations tied to vehicle condition or driver qualifications—this one points to the cargo itself or how it was readied for transport.
What our enforcement data actually shows
Across our 13 million+ inspection records, 397.3AU is exceptionally uncommon. We have recorded only 2 citations all-time for this code, with zero citations in the last 12 months and zero in the last 90 days. Neither of the two drivers cited was placed out of service, resulting in a 0.0% out-of-service rate—significantly lower than the all-FMCSR average of 31.4%.
397.3AU ranks #2651 out of 3,036 FMCSR codes by citation volume, placing it in the bottom tier of enforcement activity. The rarity of this citation suggests either very low violation rates in the field, or that inspectors seldom encounter the specific condition it describes. Either way, your citation puts you in an extremely small cohort.
Who gets cited most
Because only 2 citations exist in our database, geographic and carrier patterns are minimal. Our data shows fleets such as WINCO TRUCKING LLC and NORTHHAUL INC each received 1 citation. The cited vehicles included makes such as POLA and VOLV. With such limited enforcement history, drawing conclusions about which states or carrier types are more vulnerable would be speculative. However, the fact that both historical cases avoided out-of-service placement suggests inspectors may view this violation as correctable or administrative in nature rather than immediately unsafe.
How severe is this compared to similar codes
Within the hazardous materials category, 397.3AU is far less frequently cited than its peer codes. For comparison:
- 177.834A-HMC (general loading/unloading hazmat) has 3,954 citations with a 99.2% out-of-service rate—indicating severe, safety-critical violations.
- 177.817(a) (placarding violation) has 2,274 citations with a 75.1% out-of-service rate.
- 172.602(c)(1) (maintenance/accessibility of Emergency Response information) has 1,464 citations with a 0.0% out-of-service rate, matching 397.3AU's zero OOS rate.
The 0.0% OOS rate for 397.3AU places it among the lowest-severity hazmat codes in terms of immediate roadside enforcement action, though the small sample size (2 cases) means this figure is less stable than peer codes with hundreds or thousands of citations.
How to avoid it
Because 397.3AU enforcement is rare, your best defense is rigorous pre-transport hazmat compliance:
- Verify all hazmat documentation before loading. Ensure shipping papers are complete, accurate, and accessible. Check that the proper emergency contact information and material descriptions are present and legible.
- Confirm packaging and containment integrity. Inspect all hazmat containers for leaks, damage, or deterioration before loading. Ensure closures are tight and seals are secure.
- Review placarding and labeling. Even if placards are present, confirm they are legible, properly positioned, and match the actual hazmat class and description of what you are transporting.
- Know your load classification. Understand whether your shipment requires special handling, segregation from incompatible materials, or specific temperature or pressure controls. Confirm the shipper has classified it correctly.
- Request a pre-load inspection from the shipper or broker. If you notice any ambiguity about how the load was prepared, ask the facility to walk through their hazmat checklist with you before you accept the shipment.
- Document your pre-trip check. Record that you inspected the hazmat shipment condition and documentation. This creates a record that you took due diligence.
Given the extreme rarity of this code in our data, a citation likely means an inspector caught an uncommon or nuanced breach rather than a widespread practice. Staying methodical about hazmat preparation protocols will keep you well clear of it.