393.87 — Improperly flagged projecting load
49 CFR 393 • Vehicle Maintenance BASIC • Severity 4/10
What this violation means
Companion to 393.95E — flag not red, not 18-inch square, or improperly placed. 4 SMS points.
Why this gets cited
Wrong color (orange/yellow). Wrong size. Improperly attached.
How to fix / prevent
DOT-compliant red flags, 18-inch square minimum. At night, use a red light instead.
Out-of-service criteria
No — this violation is not typically out-of-service eligible. The inspector will note 393.87 on the inspection report (form MCS-63), but the truck/driver can usually continue after the inspection ends. It still counts against the carrier in CSA scoring (severity 4/10 weight, time-weighted over 24 months) and shows on the driver's PSP record. A pattern of these non-OOS violations across multiple inspections is what triggers FMCSA intervention — a single citation rarely does.
CSA / SMS impact
393.87 carries a severity weight of 4/10 in FMCSA's Safety Measurement System (SMS). Higher weights mean faster CSA percentile movement. Combined with a time-weighting factor (2× for citations within the last 6 months, decaying over 24 months), this violation can move your Vehicle Maintenance 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%).