DOT transport classification

Sulfuric acid: UN number by concentration

Under 49 CFR 172.101, sulfuric acid ≤51% ships as UN2796 (class 8, packing group II); >51% ships as UN1830 (class 8, packing group II).

CAS 7664-93-9 · Source: 49 CFR 172.101 Hazardous Materials Table

Classification by concentration

Sulfuric acid — 49 CFR 172.101. Percentages are by mass (w/w).
ConcentrationUN numberClassPacking groupAlliance Chemical products
≤51%UN27968IISulfuric Acid 37% Battery Acid in a 1-gallon plastic jug from Alliance Chemical for lead-acid battery maintenanceSulfuric Acid 37% - Battery AcidSulfuric Acid 50% Electrolyte Grade 1-gallon plastic jug for battery electrolyte, Alliance ChemicalSulfuric Acid 50% - Electrolyte Grade
>51%UN18308IISulfuric acid 70% technical grade in a 1-gallon plastic jug for industrial pH neutralization, Alliance ChemicalSulfuric Acid 70%Sulfuric acid technical grade drain cleaner 1-gallon plastic jug, Alliance Chemical for drain clearingDrain Hammer - Sulfuric Acid Drain CleanerSulfuric Acid 93% Technical Grade in a white 1-gallon plastic jug, Alliance Chemical for metal pickling and pH adjustmentSulfuric Acid 93% Technical GradeSulfuric Acid 96% ACS Reagent Grade 1-gallon jug, Alliance Chemical for metal treatment and chemical synthesisSulfuric Acid 96% ACS Grade
  • ≤51%: Also the correct entry for 'Battery fluid, acid'.
  • >51%: Packing group does NOT escalate at this boundary — both sides are PG II; only the UN number changes. Fuming sulfuric acid (oleum) is UN1831, a different entry.

How to read this

  • Percentages are by mass. 49 CFR 172.101 thresholds are w/w, but product labels often state volume (v/v). Near a cutoff the two can fall on opposite sides, so confirm the basis before classifying a shipment.
  • Products listed are verified individually. A product appears in a band only when its own reviewed classification matches it. Where a product's classification is still under review, we leave it out rather than infer it from the table.
  • 1 sulfuric acid product is not listed above for that reason.
  • This page is a reference, not a shipping paper. Classification for an actual shipment depends on packaging, quantity and mode; consult the current eCFR entry and the product's safety data sheet.

Source

49 CFR 172.101 Hazardous Materials Table. Reference text: “Sulfuric acid <=51% => UN2796, Class 8 PG II (same PG II as >51% UN1830). Also the correct UN for 'Battery fluid, acid'. >51% => UN1830.”

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