What 173.32G1 means in plain language
When you transport hazardous materials in a portable tank, that tank must stay fully contained within the boundaries of your transport vehicle. If a portable tank extends beyond the sides, front, or rear of your truck or trailer, you're in violation of 173.32G1.
This rule exists because a tank protruding outside the vehicle is at higher risk of damage from roadside contact, other vehicles, or obstacles. A damaged hazmat tank creates immediate dangers—not just for you, but for emergency responders and the public. The regulation requires that portable tanks used for hazmat transport remain completely within the vehicle's footprint.
The requirement applies to all portable tanks carrying hazardous materials, regardless of the specific commodity or tank construction type. If you're hauling hazmat in a portable container, ensuring it doesn't extend beyond your vehicle's dimensions is non-negotiable at roadside.
What our enforcement data actually shows
Our inspection records show that 173.32G1 is cited very rarely in the field. Across our database of 13 million+ roadside inspections, we've recorded only 1 citation for this violation in our entire history. In the last 12 months, there were 0 citations, and in the last 90 days, there were 0 citations.
The out-of-service rate for this code is 0.0%—the single citation on record did not result in an out-of-service order. This stands in sharp contrast to the all-FMCSR average out-of-service rate of 31.4%, meaning inspectors rarely escalate this violation to a vehicle removal.
Nationally, 173.32G1 ranks 2,796th out of 3,036 FMCSR codes by citation volume, placing it in the lowest-cited category. The rarity of enforcement suggests either strong industry compliance with portable tank containment standards or very limited roadside inspections that specifically test for tank extension.
Who gets cited most
Because only 1 citation exists in our historical records, geographic and carrier patterns are not statistically meaningful. Our data does show that RDL TRANSPORTATION INC (USDOT 2447861) appeared once in connection with this code. Vehicle makes cited include KALY and KW, each appearing once.
The extremely low citation count means you cannot reliably predict enforcement patterns by state or fleet size based on TruckCodex data. However, this also suggests that if you comply with containment requirements, the likelihood of a roadside citation is very low.
How severe is this compared to similar codes
In the broader hazardous materials category, 173.32G1 enforcement is significantly lighter than related portability and loading violations. For comparison:
- 177.834A-HMC (general loading and unloading of hazmat) has 3,954 citations with a 99.2% out-of-service rate—far more frequent and nearly always results in vehicle removal.
- 177.817(a) (placarding violations) has 2,274 citations with a 75.1% out-of-service rate, also much more commonly enforced.
- 172.602(c)(1) (maintenance and accessibility of emergency response information) has 1,464 citations with a 0.0% out-of-service rate, indicating that violations are cited but rarely escalated to removal.
173.32G1's single citation and 0.0% out-of-service rate suggest it is treated as a lower-severity hazmat violation compared to loading, placarding, and documentation failures that inspectors encounter thousands of times per year.
How to avoid it
Prevent a 173.32G1 citation with these concrete pre-trip and operational steps:
- Measure your portable tank and vehicle before loading. Know the exact width, height, and length of both your transport vehicle and the portable tank. If the tank is close to your vehicle's outer dimensions, measure twice and verify clearance on all sides before accepting the load.
- Position the tank centrally within the vehicle. During loading, ensure the tank is centered side-to-side and does not rest partially on the vehicle bed edge. Uneven loading can cause the tank to shift toward the sides during transport.
- Inspect mounting and securing hardware. Verify that the tank is securely fastened to the vehicle frame using appropriate brackets or tie-downs rated for hazmat loads. A loose tank can shift and eventually protrude during highway vibration.
- Document vehicle dimensions on your logbook or load sheet. Record the maximum width and height of your transport vehicle before accepting a portable tank load. This creates a reference point you can verify at each stop.
- Request a site inspection if you're unsure. If a dock or loading facility is about to load a portable tank and you have any doubt about clearance, ask the shipper or loader to measure and confirm containment before the tank is secured.
- Check clearance at your first stop after loading. Before entering highway traffic, stop safely and walk around your vehicle. Visually confirm that no part of the tank extends beyond the vehicle's profile—front, rear, or sides.