FMCSR 172.203(p): LPG Odorization Requirements Explained

What happens after a 172.203(p) citation for non-odorized LPG entry. Our data shows this is a rare violation with minimal out-of-service impact.

Severity Weight
N/A
OOS Eligible
No
BASIC Category
Hazardous Materials
Code System
FMCSR
Code:
172.203(p)
Code System:
FMCSR
BASIC Category:
Hazardous Materials
OOS Eligible:
No
Severity Weight:
N/A

Ranks #2,427 of 3,146 FMCSR codes by citation frequency • OOS rate of 0.0% is below the FMCSR-wide average of 33.3%.

Violation Description

No Non-odorized entry for LPG

In-Depth Explainer

Grounded in TruckCodex roadside-inspection data

What 172.203(p) means in plain language

This regulation requires that liquefied petroleum gas (LPG) loaded into a cargo tank must be odorized—meaning it must contain an odorant substance that makes the gas detectable by smell. The purpose is safety: odorized LPG allows drivers, inspectors, and emergency responders to quickly detect leaks or escapes that would otherwise be invisible and dangerous.

If you've been cited for 172.203(p), it means an inspector found that LPG in your vehicle lacked this required odorant, or that you attempted to load non-odorized LPG into your tank. This is a product specification violation, not a driving or equipment failure—it hinges on what was placed into your vehicle at the loading terminal.

What our enforcement data actually shows

Across our 13 million inspection records, we have documented only 5 all-time citations for 172.203(p) since our tracking began. In the last 12 months, we recorded zero citations, and in the last 90 days, zero citations. This code ranks #2406 out of 3,036 FMCSR codes by enforcement volume—making it exceptionally rare.

Of those 5 all-time citations in our database, zero resulted in an out-of-service order. The out-of-service rate for this code is 0.0%, which is significantly lower than the all-FMCSR average OOS rate of 31.4%. In practical terms: inspectors cite this violation but do not typically ground your vehicle over it. You can continue operating after citation, though the violation itself must be corrected before reloading.

Who gets cited most

Because citation volume is so low (5 total), state and carrier data show dispersed, single citations. Our records indicate that five carriers have each received one citation: United Petroleum Transports Inc (USDOT 185040), PC Transport Inc (USDOT 191414), Val Transport LLC (USDOT 687455), R L C Trucking LLC (USDOT 1964323), and Inter Petroleum LLC (USDOT 2442859). No single fleet shows a pattern of repeated citations for this code.

Vehicle makes cited include FRHT, FROS, INTL, and OTHR—each with one citation. The lack of concentration here reflects how uncommon this violation is in the field.

How severe is this compared to similar codes

Within the Hazardous Materials category, this code is at the milder end of the enforcement spectrum. For comparison:

  • 177.834A-HMC (General loading/unloading hazmat) has generated 3,954 citations with a 99.2% out-of-service rate—meaning inspectors almost always ground vehicles for these violations.
  • 177.817(a) (Placarding violation) has 2,274 citations with a 75.1% OOS rate—serious enough to warrant grounding in three out of four cases.
  • 172.516(c)(6) (Placard damaged, deteriorated, or obscured) has 1,796 citations but only a 1.6% OOS rate, similar to 172.203(p)'s rarity as a non-grounding hazmat issue.

Your citation sits in a category of hazmat violations that inspectors document but rarely escalate to out-of-service status. The infraction is noted and corrected at the loading terminal level, not through immediate fleet downtime.

How to avoid it

  1. Verify odorant at the loading terminal — Before accepting any LPG load, confirm with the terminal operator that the product meets DOT specifications for odorization. Ask to see or verify the bill of lading notation that confirms odorant has been added. If you smell nothing distinctly sulfurous or mercaptan-like when near the tank during loading, question it before sealing.

  2. Know your supplier's compliance history — Work with LPG suppliers and terminals that maintain strict quality control. A pre-trip conversation with dispatch about your regular loading locations can help identify any known sourcing issues.

  3. Document your load receipt — Retain load tickets and bills of lading that specify odorant content. This protects you if a downstream inspector cites the violation; your documentation shows you accepted product as represented by the shipper.

  4. Report terminal irregularities — If a terminal ever loads your tank with product that does not have a detectable odor, report it to your dispatcher and the terminal operator immediately. Do not transport non-compliant cargo.

  5. Understand your role in the supply chain — Unlike brake or equipment violations, this one originates at the shipper's facility. Your responsibility is to verify and refuse non-compliant product before departure, then report the issue up the chain.

Last updated: 2026-04-20T17:11:07.414Z Based on TruckCodex inspection data See 172.203(p) Q&A → Fleet FAQ →

Data sources & freshness

TruckCodex aggregates official public-sector datasets. See the Source registry for dataset-level coverage and the Freshness log for last-import timestamps.

Census, SAFER, SMS, Licensing & Insurance (L&I), roadside inspections, crashes, and authority history.

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Vehicle recall campaigns, defect investigations, and consumer safety complaints (SCRS).

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EIA

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Cross-border carrier registry and Canadian recall campaigns where applicable.

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