172.504 — Improper hazmat placarding
49 CFR 172 • Hazardous Materials BASIC • Severity 7/10
What this violation means
Missing, wrong, faded, or damaged placards. OOS for any 'release' situation. 7 SMS points.
Why this gets cited
Wrong placard from prior load not removed. Placard not appropriate for current cargo. Faded.
How to fix / prevent
Verify placards match shipping papers before leaving shipper. Standardized placard kit in cab.
Out-of-service criteria
Yes — this violation IS out-of-service eligible. When an inspector finds 172.504 during a Level 1, 2, or 3 inspection, they can place the Hazmat OOS using the North American Standard Out-of-Service Criteria. OOS means the truck cannot move from the inspection site until the defect is corrected (vehicle OOS) or the driver is replaced (driver OOS). For carriers, every OOS violation adds time-weighted points to your CSA Hazardous Materials BASIC — and it shows in the public SMS data within 30 days. For drivers, an OOS event stays on PSP for 3 years.
CSA / SMS impact
172.504 carries a severity weight of 7/10 in FMCSA's Safety Measurement System (SMS). Higher weights mean faster CSA percentile movement. Combined with a time-weighting factor (3× for citations within the last 6 months, decaying over 24 months), this violation can move your Hazardous Materials BASIC percentile significantly if it stacks with similar citations across your fleet. The threshold for FMCSA intervention is the 65th percentile for most BASICs (50th for Hazmat and Passenger Carrier). Once you cross that, FMCSA can send a Warning Letter, Off-Site Investigation, or full Compliance Review.
How to read this: a single citation rarely puts you over threshold — it's the pattern. Track your inspection rate per power unit and aim for OOS rate under 5% (industry average is 21%).