No temperature controls noted for Class 4.1 or Class 5.2
172.203(o) is a Documentation - HM violation under 49 CFR §172.203(o). It falls in the Hazardous Materials Compliance BASIC with a severity weight of 3/10.
Last updated May 2026
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Notes
DSMS: N | Comment: Updated description in 3.11 | Footnote: The description for this violation was updated in SMS with the September 25, 2020 snapshot.If this violation was written incorrectly, here are the angles trucking-safety managers use to contest it. Playbook: Hazardous Materials.
Common ways to challenge this code
The materials transported did not exceed the threshold quantities requiring placards under 49 CFR Part 172 Subpart F.
Evidence that wins
This administrative code is on the inspection report but does not contribute to CSA BASIC scoring per FMCSA SMS Methodology Appendix A.
Evidence that wins
Common pitfalls — avoid these
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Codes under the same FMCSA violation group
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HM (Markings) - Offering a multi-unit tank car tank containing liquefied petroleum gas without "NOT/NON-ODORIZED" marking as required.
172.203(o) is the FMCSA roadside-inspection violation code for "No temperature controls noted for Class 4.1 or Class 5.2", part of the Documentation - HM group, cited under 49 CFR §172.203(o).
172.203(o) falls under the Hazardous Materials Compliance BASIC in the FMCSA Safety Measurement System (SMS).
172.203(o) carries a severity weight of 3 out of 10. Higher weights indicate violations more closely tied to crash risk, and they count more toward a carrier's Hazardous Materials Compliance score.
No. 172.203(o) is not an out-of-service violation, so on its own it does not trigger an out-of-service order at the roadside.
The point contribution of 172.203(o) depends on its severity weight (3/10) multiplied by a time weight of 3, 2, or 1 based on how recent the inspection is. You can calculate the exact contribution with the CSA points calculator.
Yes. If you believe 172.203(o) was recorded in error, you can file a Request for Data Review (RDR) through the FMCSA DataQs system with supporting evidence. A successful challenge can remove or correct the violation on your record.
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