What hazmat cannot be loaded together?
The specific combinations are laid out in the DOT segregation table (49 CFR §177.848), which cross-references every hazard class and division. As a general pattern: explosives can't go with most other hazard classes, oxidizers can't be loaded with flammable materials, and acids generally can't be loaded with materials that are dangerous when wet — but the exact rule depends on the specific classes and divisions involved, so the real table should always be checked rather than relying on general rules of thumb.
The specific combinations are laid out in the DOT segregation table (49 CFR §177.848), which cross-references every hazard class and division. As a general pattern: explosives can't go with most other hazard classes, oxidizers can't be loaded with flammable materials, and acids generally can't be loaded with materials that are dangerous when wet — but the exact rule depends on the specific classes and divisions involved, so the real table should always be checked rather than relying on general rules of thumb.
Why people ask this
This question comes from the loading dock, not the office — someone standing in front of two pallets needing a fast, correct answer before they load a truck.
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