What 178.345-11B means in plain language
FMCSR 178.345-11B covers the valves on hazardous materials tank vehicles — specifically DOT406, DOT407, and DOT412 specification tanks. These valves are critical safety components that control flow into and out of the tank during loading, unloading, and transport. The regulation requires that these valves meet DOT design and operational standards.
When an inspector cites you for 178.345-11B, they've found a problem with one or more of these valves — whether it's damage, leakage, improper installation, or failure to operate as designed. Tank valve defects can lead to spills, which is why DOT takes them seriously. However, this violation does not automatically trigger an out-of-service order on its own; the inspector's judgment about safety risk determines whether your vehicle gets placed out of service.
What our enforcement data actually shows
Across our 13 million+ inspection records, 178.345-11B ranks #1898 of 3,036 FMCSR codes by citation volume. The citation rate is low — 22 all-time citations with 14 in the last 12 months and 5 in the last 90 days — but the out-of-service rate is notably high. Our data shows that 8 of those 22 citations resulted in an out-of-service placement, for a 36.4% OOS rate. This is 5 percentage points higher than the all-FMCSR average of 31.4%, indicating that when inspectors flag tank valves, they're more likely to deem the vehicle unsafe to operate.
The trend in recent months shows variability. February 2026 saw 4 citations with 1 out-of-service placement, while November and December 2025 each had only 1 citation with no out-of-service action. This suggests the violation occurs in clusters, possibly linked to seasonal transport patterns or particular routes.
Who gets cited most
Texas dominates the citation count, with 7 citations in the last 180 days and a 28.6% out-of-service rate (2 OOS placements). Illinois follows with 1 citation that resulted in an out-of-service order, giving it a 100% OOS rate in that period — a stark difference from Texas, though the volume is too small to draw broad conclusions. Our data shows that carriers operating in Texas are more frequently subject to tank valve inspections, but the lower OOS rate there suggests that violations may sometimes be repairable or borderline.
Our inspection records show fleets such as Windstar Trucking LLC, Transportacion Carretera SA de CV, Eco Transportes Internacionales SA de CV, and Gerardo Aguilar Garcia each with 2 citations across our database. These citations appear scattered over time and geography, not concentrated in a pattern that would indicate systemic non-compliance.
How severe is this compared to similar codes
Tank valve issues sit in the middle range of hazardous materials violations. General loading and unloading hazmat violations (177.834A-HMC and 177.834(a)) are far more common — 3,954 and 3,839 citations respectively — and carry a severe out-of-service risk of 99.2% and 97.9%. Placard violations (177.817(a)) also exceed 2,000 citations with a 75.1% OOS rate. By contrast, tank valve defects are rarer, and while the 36.4% OOS rate is elevated, it's substantially lower than fundamental hazmat loading and placard violations.
Other tank-related codes like general maintenance requirements (396.3A1) appear in our co-occurring data, suggesting that tank valve defects often appear alongside broader equipment neglect rather than in isolation.
How to avoid it
Perform a detailed pre-trip inspection of all tank valves. Check for visible cracks, corrosion, loose fittings, or leakage around valve stems and caps. Ensure all caps and plugs are tight and sealing properly. A few minutes of hands-on inspection can catch a defect before roadside.
Check brake systems and steering components carefully. Our inspection records show that tank valve citations frequently co-occur with brake chamber defects (393.47A), slack adjuster problems (393.47E), and worn steering components (393.53B). These suggest that vehicles cited for tank valves often have broader mechanical neglect. Inspect brake chambers, slack adjusters, and steering linkages during your pre-trip.
Verify lighting is functional. Tank valve citations co-occur with inoperable required lamps (393.9) in 3 shared inspections — the most common co-occurrence in our last 90 days of data. Broken lights increase inspector attention to the entire vehicle, raising the odds that tank issues get caught.
Review your coupling and emergency equipment. Defective coupling devices (393.55E) and missing or defective fire extinguishers (393.95A) appeared alongside tank valve citations in our records. These are quick checks that can prevent a cascade of citations.
Know your vehicle's maintenance history. Freightliner vehicles account for 10 of the 22 all-time tank valve citations in our database, followed by Heil (5 citations). If you operate a Freightliner or Heil tank truck, maintain detailed service records and verify that all recent valve work was performed correctly and documented. Request proof of periodic inspection (396.17C) to show the DOT examiner during a stop.
Do not defer valve repairs. Tank valve defects don't improve with time; they degrade. A minor leak or a stuck valve will worsen and become an out-of-service violation. Address any reported issues immediately rather than hoping the inspector on the next stop doesn't catch it.