Violation codes / 393.83G
49 CFR 393 · Parts and accessories393.83G
Exhaust - Discharging at a point forward or directly below the driver or sleeper compartment
What the rule actually says
This violation cites 49 CFR 393.83, exhaust systems. The regulation reads:
(a) Every motor vehicle having a device (other than as part of its cargo) capable of expelling harmful combustion fumes shall have a system to direct the discharge of such fumes. No part shall be located where its location would likely result in burning, charring, or damaging the electrical wiring, the fuel supply, or any combustible part of the motor vehicle.
(b) No exhaust system shall discharge to the atmosphere at a location immediately below the fuel tank or the fuel tank filler pipe.
(c) The exhaust system of a bus powered by a gasoline engine shall discharge to the atmosphere at or within 6 inches forward of…
The section continues.
49 CFR 393.83, Exhaust systems. Read the full section on eCFR
Quoted verbatim from the Electronic Code of Federal Regulations. Nothing here is a paraphrase, and nothing here is legal advice on a citation.
How often this comes up
This violation was recorded 50,796 times across the roadside inspections in the FMCSA file, making it the 74th most frequently cited code. Whether a given instance puts a vehicle or driver out of service is decided at the roadside by the inspector, not by the code itself, so the same violation can end a trip or simply be noted.
It sits under 49 CFR Part 393, which covers parts and accessories. To see it in context, look up a carrier and read its inspection history: the same code appearing repeatedly is a different signal from a single occurrence.
Look up a carrier's inspection record
Other parts and accessories violations
- 393.9 Inoperable Required Lamp
- 393.47E Brake Out of Adjustment - Roto, Clamp (Short…
- 393.75A3-TAOL Tires - All others, leaking or inflation les…
- 393.78 Wipers - Inoperative / missing / damaged wip…
- 393.9TS Inoperative turn signal
- 393.9A-LIL Lighting - Identification lamp(s) inoperativ…
- 393.75A3 Tire-flat and/or audible air leak
- 393.95A No/discharged/unsecured fire extinguisher
- 393.95F Emergency Equipment - Stopped vehicle warnin…
- 393.60C Windshield - Damaged or Discolored
- 393.55E-B Air Brake - ABS malfunction lamp defective o…
- 393.45B2UV Brake Hose or Tubing Chafing and/or Kinking …
Counts are from the FMCSA Inspections and Violations file via data.transportation.gov. This describes how the violation is recorded, and is not legal advice on a citation.