DOT transport classification

Nitric acid: UN number by concentration

Under 49 CFR 172.101, nitric acid <65% ships as UN2031 (class 8, packing group II); ≥65% and ≤70% ships as UN2031 (class 8 with a 5.1 subsidiary, packing group II); >70% ships as UN2031 (class 8 with a 5.1 subsidiary, packing group I).

CAS 7697-37-2 · Source: 49 CFR 172.101 Hazardous Materials Table

Classification by concentration

Nitric acid — 49 CFR 172.101. Percentages are by mass (w/w).
ConcentrationUN numberClassPacking groupAlliance Chemical products
<65%UN20318IINitric Acid 5% Technical Grade 1-liter plastic bottle from Alliance Chemical for metal pickling and passivationNitric Acid 5%Nitric Acid 20% Technical Grade in a 1-liter white plastic bottle from Alliance Chemical for metal finishing and descalingNitric Acid 20%Nitric Acid 25% Technical Grade in a 1-liter white plastic bottle from Alliance Chemical for metal passivationNitric Acid 25%Nitric Acid 40% Technical Grade in a 1-liter white plastic bottle from Alliance ChemicalNitric Acid 40%
≥65% and ≤70%UN20318 (5.1)IINitric Acid 65% Technical GradeNitric Acid 65% ACS Grade in a 1-liter bottle from Alliance Chemical for laboratory analysis and metal passivationNitric Acid 65%ACS GradeNitric Acid 69% Technical GradeNitric acid 69% ACS grade in a 55-gallon blue plastic drum for stainless steel passivation, Alliance ChemicalNitric Acid ACS 69% - 55 Gallon DrumNitric Acid 70% ACS Grade 1-liter bottle, Alliance Chemical for metal finishing and stainless steel passivationNitric Acid 70% ACS Grade - Low ParticleNitric Acid 70% Technical Grade
>70%UN20318 (5.1)I—
  • <65%: No oxidizer subsidiary below 65%.
  • ≥65% and ≤70%: The common 70% ACS grade sits here: label 8 + 5.1, PG II — NOT PG I.
  • >70%: Red fuming nitric acid is a different entry entirely: UN2032, PG I, with both 5.1 and 6.1 subsidiaries.

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.
  • 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: “HIGHEST-RISK ENTRY. Class 8 throughout, but subsidiary and PG move with concentration: (a) <=20% => 8, PG II, NO subsidiary; (b) >20% and <65% => 8, PG II, NO subsidiary; (c) >=65% and <=70% => 8, PG II, WITH 5.1 oxidizer subsidiary; (d) >70% => 8, PG I, WITH 5.1 subsidiary. The common 70% ACS grade falls in bracket (c): label 8 + 5.1, PG II. Red fuming nitric acid => DIFFERENT UN: UN2032 (Class 8, PG I, subsidiaries 5.1 AND 6.1).”

All DOT classification references