Violation code

177.823A-HMPMCM

HM (Placarding) - A carrier may not move a transport vehicle containing a hazardous material unless the vehicle is marked and placarded in accordance with part 172 or as authorized in �171.12a of this subchapter, or unless, in an emergency.

Hazardous Materials Compliance5Non-OOS· SMS Appendix A v3.20

177.823A-HMPMCM is a Markings - HM violation under 49 CFR §177.823A-HMPMCM. It falls in the Hazardous Materials Compliance BASIC with a severity weight of 5/10. Nationally it was cited 1,530 times in the last five years, with an OOS rate of 1.0%.

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National roadside inspection stats

as of 6/20/2026

Inspections

1,381

that found this code

Violations

1,530

total written

OOS rate

1.0%

16 OOS

Source: FMCSA roadside inspection data (last 5 years). The OOS rate is the share of these violations that led the officer to mark the driver or vehicle out of service.

Violation group: Markings - HM
Regulation §: 177.823A-HMPMCM
Severity weight: 5
Used in SMS: Yes
Status: Active
Updated: 6/20/2026

Last updated June 2026

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Notes

DSMS: N | Comment: Added in 3.15; updated description in 3.19 | Footnote: As of February 1, 2023, the violations in this table are included in SMS. Only violations cited on or after February 1 are included in SMS calculations. This update aligns SMS with how violations are being cited in a new software used for roadside inspections. The description for this violation was updated in SMS with the September 27, 2024 snapshot.

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Challenging 177.823A-HMPMCM through FMCSA DataQs

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

Shipment was not placardable
The materials transported did not exceed the threshold quantities requiring placards under 49 CFR Part 172 Subpart F.
Evidence that wins
- ✓Shipping papers showing UN number, hazard class, and quantity
- ✓Manufacturer's product specification sheet
Administrative HazMat code (not in SMS)
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
- ✓FMCSA SMS Methodology Appendix A reference

Common pitfalls — avoid these

⚠Administrative HazMat codes still appear on the PSP record even when not scored in SMS

⚡ Draft a challenge for 177.823A-HMPMCM →Read the DataQs guide first

More codes in Hazardous Materials Compliance

Same BASIC category — ranked by national citation volume

View all Hazardous Materials Compliance codes →

Other Markings - HM codes

Codes under the same FMCSA violation group

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Frequently asked questions about 177.823A-HMPMCM

What does violation 177.823A-HMPMCM mean?

177.823A-HMPMCM is the FMCSA roadside-inspection violation code for "HM (Placarding) - A carrier may not move a transport vehicle containing a hazardous material unless the vehicle is marked and placarded in accordance with part 172 or as authorized in �171.12a of this subchapter, or unless, in an emergency.", part of the Markings - HM group, cited under 49 CFR §177.823A-HMPMCM.

What BASIC does 177.823A-HMPMCM affect?

177.823A-HMPMCM falls under the Hazardous Materials Compliance BASIC in the FMCSA Safety Measurement System (SMS).

What is the CSA severity weight of 177.823A-HMPMCM?

177.823A-HMPMCM carries a severity weight of 5 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.

Is 177.823A-HMPMCM an out-of-service (OOS) violation?

No. 177.823A-HMPMCM is not an out-of-service violation, so on its own it does not trigger an out-of-service order at the roadside.

How many CSA points does 177.823A-HMPMCM add to a carrier's score?

The point contribution of 177.823A-HMPMCM depends on its severity weight (5/10) 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.

Can 177.823A-HMPMCM be challenged through DataQs?

Yes. If you believe 177.823A-HMPMCM 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.

Keep going

CSA points calculator How to challenge a violation Draft a DataQs letter for 177.823A-HMPMCM Hazardous Materials Compliance BASIC Carrier CSA lookup CSA glossary