FMCSR 178.338-13 (MC338 Supports and Anchoring) — Q&A

Not necessarily. Across our inspection records, 178.338-13 citations resulted in an out-of-service placement in 25% of cases (1 out of 4 all-time citations). This is lower than the national average OOS rate of 31.4% across all FMCSR codes, meaning this violation is less likely to trigger an immediate roadside removal than most infractions. However, the presence of support or anchoring defects on an MC338 tank vehicle creates genuine safety risk, so inspectors may place your vehicle out of service if the condition poses an immediate hazard to the cargo or public.

178.338-13 is significantly less severe than related hazmat loading and placarding violations. Our database shows that general loading/unloading hazmat violations (177.834A-HMC and 177.834(a)) have OOS rates of 99.2% and 97.9% respectively—meaning nearly all are pulled out of service immediately. Placarding violations (177.817(a)) sit at 75.1% OOS rate. By comparison, the 25% OOS rate for 178.338-13 puts it near the lower end of the hazmat enforcement spectrum, though still subject to citation.

1. Document everything: Photograph the cited support or anchoring condition and note the inspector's specific findings on your citation form.
2. Do not move the vehicle if it was placed out of service—follow roadside inspection protocol.
3. Review the MC338 specification: Verify that all supports and anchoring hardware meet DOT requirements for your tank configuration.
4. Contact your carrier or maintenance team: Schedule immediate inspection and repair of the defective supports or anchoring system.
5. Request a re-inspection: Once repairs are complete, request a follow-up inspection to clear the violation.
6. Keep records: Save all repair documentation and inspection reports for your CSA file and future audits.

Yes, this violation is extremely rare in enforcement. Across our database of 13 million+ roadside inspections, 178.338-13 has only 4 all-time citations and zero citations in the last 90 days and last 12 months. It ranks #2480 out of 3,036 FMCSR codes by citation volume. The rarity suggests that most MC338 tank vehicles are compliant on support and anchoring, or that inspectors encounter this defect infrequently. If you're cited, it indicates a concrete, observable condition that an inspector identified during a detailed hazmat inspection.

Yes. DataQs (FMCSA's online portal) allows you to contest any roadside inspection finding, including 178.338-13. Whether your challenge succeeds depends on the nature of the violation: if the inspector documented a visual defect in supports or anchoring hardware, you can argue measurement error, misidentification, or that the condition did not meet the regulatory threshold. If the finding was based on documentation review or carrier policy, contestation may be stronger. File your challenge within 90 days of the inspection with supporting photos, repair records, or expert inspection reports showing compliance with MC338 specifications.

Our all-time data shows only 4 citations for 178.338-13, distributed among four carriers: American Welding & Gas Inc (USDOT 145402), NUCO2 Supply LLC (USDOT 578807), Southern Gas and Supply of Birmingham (USDOT 1677501), and GPM Transportation Company LLC (USDOT 3907271)—one citation each. The violation is so infrequently cited that no state emerges as a concentration point. The vehicle makes involved were International (INTL), Peterbilt (PTRB), and trailer (TRLR), again with one citation each. This scarcity reinforces that the defect is detected only in specific roadside encounters.

A 178.338-13 citation will appear in your FMCSA safety record and may be weighted into your CSA (Compliance, Safety, Accountability) profile under the Hazardous Materials BASIC category. However, with only 4 citations in our entire database, a single 178.338-13 violation is unlikely to materially damage your safety profile compared to high-volume violations like placarding or general loading infractions. The impact depends on your overall citation history. If this is an isolated incident tied to a specific truck or maintenance lapse, focus on prompt repair and documentation to prevent recurrence.

An MC338 is a DOT specification for corrosive liquid tank vehicles. The regulation requires that all structural supports (the frame and suspension components that hold the tank) and cargo anchoring hardware (chains, straps, or clamps that secure the tank to the chassis) meet design and maintenance standards. Defects include bent or missing support brackets, loose or corroded anchoring bolts, deteriorated welds, or improper fastening. Inspectors look for visible damage, movement of the tank under load, or non-compliance with the original MC338 blueprint. This is a structural safety issue because failed supports or anchoring can cause the tank to shift, rupture, or separate during transit.