FMCSR 172.326(b): Portable Tank Marking — Q&A

No. Across our 13 million+ inspection records, 172.326(b) citations have resulted in zero out-of-service placements—a 0.0% OOS rate. This is far below the national average OOS rate of 31.4% across all FMCSR codes, meaning inspectors are unlikely to ground your vehicle for this violation. However, non-OOS citations still create safety violations on your record and can impact your carrier's compliance profile.

This is among the least-enforced hazmat marking violations in the category. Our inspection database shows only 1 all-time citation for 172.326(b), ranking it #2796 of 3,036 FMCSR codes. By comparison, similar hazmat loading and placarding violations carry OOS rates of 75–99%. The 0.0% OOS rate and minimal enforcement volume indicate this violation, while still a compliance gap, is treated as lower-severity than related portable tank and placarding defects.

Immediate steps:

1. Document the citation — get a copy of the inspection report and note the specific portable tank(s) cited.
2. Verify tank identification — confirm whether your tank actually lacks owner or lessee name markings, or if the marking is faded/obscured.
3. Correct the marking — add or refresh the required owner/lessee name on the portable tank in compliance with 49 CFR 172.326(b).
4. Request re-inspection — if corrected, ask the carrier or inspector if a follow-up inspection is available to clear the violation.
5. Report to your carrier — immediately notify fleet management; they may need this for CSA reporting.

172.326(b) is significantly less severe than peer hazmat violations. General loading/unloading hazmat violations (177.834A-HMC) have a 99.2% OOS rate and 3,954 citations; placarding violations (177.817) average 75% OOS rates with thousands of citations each. Our data shows 172.326(b) has never resulted in an OOS placement in our database of 13 million+ inspections. While both are hazmat violations, marking defects are treated far more leniently than improper loading, unloading, or placarding.

Very rarely. Across all-time enforcement records, only 1 citation exists for 172.326(b) in our database of 13 million+ roadside inspections. In the last 12 months, there have been 0 citations; in the last 90 days, 0 citations. This extremely low volume suggests portable tank owner/lessee name marking is either widely compliant or infrequently inspected. The single citation was issued to ARGUINDEGUI OIL COMPANY II LTD.

Yes, you can challenge the citation through FMCSA's DataQs (Crash and Roadside Data Quality System). Portable tank marking is a visual, equipment-based finding—inspectors must document whether the required owner or lessee name is actually present on the tank. If you believe the marking was present, legible, and compliant when inspected, you have grounds to contest. Gather photos of the tank showing the marking, maintenance records, and request DataQs remediation through your carrier's safety department.

Both. FMCSA assigns violations to the driver's CSA record and the carrier's CSA record. 172.326(b) marking defects, like most equipment violations, reflect on both parties' compliance profiles. As the driver, the citation impacts your carrier's Hazardous Materials BASIC and Equipment Maintenance BASIC categories, which influence your company's Safety Fitness Determination. Your individual violations also contribute to your personal safety record, visible to future employers and insurance underwriters.

There is insufficient trend data to determine direction. Our inspection records show 0 citations in the last 90 days and 0 in the last 12 months, compared to 1 all-time citation. The single-citation lifetime volume is too small to establish a meaningful trend. This suggests either stable, very low compliance risk across the industry, or that this specific violation is rarely the focus of roadside hazmat inspections. Track your company's own citation patterns with your safety manager for localized trends.