What 177.848(d) means in plain language
FMCSR 177.848(d) prohibits the loading, transportation, or storage of certain hazardous materials in combinations that are incompatible or unsafe. In practical terms: you cannot package or transport hazardous materials together if doing so creates an unreasonable risk of harm—either because the materials could react with each other, contaminate each other, or cause fires or explosions.
This rule exists because some hazardous commodities are simply incompatible. For example, oxidizers and flammable liquids loaded in the same cargo compartment, or corrosive substances stored near materials they could degrade, create dangerous conditions. The regulation requires drivers and shippers to understand what they're hauling and ensure nothing incompatible shares the same load space, vehicle, or storage area.
If you've been cited for this violation, it means an inspector found evidence that your load or cargo configuration violated this compatibility requirement—whether that was discovered through documentation review, visual inspection, or both.
What our enforcement data actually shows
Across our 13 million roadside inspection records, FMCSR 177.848(d) has been cited 27 times all-time, placing it at #1838 of 3,036 FMCSR codes by citation volume. Over the last 12 months, our database shows zero citations for this violation. In the last 90 days, zero citations were recorded.
When 177.848(d) citations do occur, they carry serious consequences. Our data indicates that 16 of the 27 all-time citations resulted in out-of-service placement—an out-of-service rate of 59.3%. This is significantly higher than the all-FMCSR average OOS rate of 31.4%, meaning inspectors treat this violation as a serious safety defect nearly twice as often as typical FMCSR codes. Out-of-service placement means your vehicle is removed from service immediately and cannot resume operation until the violation is corrected and re-inspected.
Who gets cited most
Our enforcement records do not include sufficient state-level breakdowns to reliably name the top three states. However, our data shows that across carriers, Greenwood Motor Lines Inc (USDOT 63391) has the highest citation count at 3 citations. Lee Jennings Target Express Inc (USDOT 810111), La Teja Contractors and Landscaping Inc (USDOT 1751551), and Ross Express LLC (USDOT 86179) each have 2 citations. This concentration reflects that hazardous materials transportation requires specialized knowledge and compliance infrastructure; the vast majority of carriers have zero citations for this violation.
How severe is this compared to similar codes
To understand the severity context, look at related hazardous materials loading violations. FMCSR 177.834A—General loading/unloading hazmat—has been cited 3,954 times with a 99.2% out-of-service rate. FMCSR 177.834(a) shows 3,839 citations with a 97.9% OOS rate. These peer codes are cited far more frequently and trigger out-of-service placement in nearly every instance.
FMCSR 177.817(a), Placarding violation, has 2,274 citations with a 75.1% OOS rate. FMCSR 177.823(a), Movement of damaged hazmat packages, has 1,829 citations with a 51.8% OOS rate. While 177.848(d) is rarer, its 59.3% OOS rate places it in the upper-middle range of hazmat enforcement severity—more likely to result in shutdown than placarding documentation failures, but less automatic than general loading/unloading violations.
How to avoid it
Prevention starts with your pre-trip inspection and load documentation review:
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Verify the shipping papers before accepting the load. Check the hazardous materials description, proper shipping name, hazard class, and any compatibility notes from the shipper. Do not load materials that the shipping papers indicate are incompatible. If you see conflicting information or unlabeled commodities, refuse the load and contact your dispatcher.
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Know the incompatibility rules for your commodity class. Oxidizers cannot ride with flammables. Acids and bases must be segregated. Corrosives cannot be stored near metals they will attack. If you regularly haul hazmat, request training from your employer on the specific compatibility matrix for the materials your carrier transports.
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Inspect the cargo compartment and packaging before loading. Ensure containers are intact, sealed, and properly labeled. Look for any signs that materials have already mixed or leaked. Report any contamination or damage immediately—do not load a package into a space where it could interact with residue from a previous load.
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Keep loads physically separated if required. Some hazmat must be loaded in different compartments or with physical barriers. Follow the shipper's instructions and your company's load plan exactly. When in doubt, ask—it is far better to delay a load than to transport an incompatible mix.
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Document everything at pick-up. Photograph or note the condition of packages, the load configuration, and any segregation barriers you use. This documentation protects you if an inspection occurs and provides evidence that you loaded in compliance.