UN/NA Number Reference
DOT Class 5.1 Oxidizer placard

UN 1496: Sodium chlorite

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 1496 is assigned the proper shipping name Sodium chlorite in the U.S. DOT Hazardous Materials Table (49 CFR 172.101). It is classified as a Class 5.1 Oxidizer material, Packing Group II. Required label(s): 5.1.

Packing group indicates the degree of danger within a hazard class: PG I is high danger, PG II medium, PG III low. The proper shipping name, hazard class, UN number, and packing group together form the basic shipping description that must appear on shipping papers and, where required, on the package and placard.

Emergency Response (ERG Guide 143)

Hazards: May explode from heat or contamination. Strong oxidizer. May ignite combustibles.

Fire: Flood with water from distance. Cool containers. Evacuate area if fire reaches cargo.

Spill: Keep combustibles away. Do not touch. Use water spray.

Chemical and Physical Properties

Sodium chlorate appears as an odorless pale yellow to white crystalline solid. It is appreciably soluble in water and heavier, so may be expected to sink and dissolve at a rapid rate. Although it is not itself flammable, the solid product and even 30% solutions in water are powerful oxidizing agents. Contact with wood, organic matter, ammonium salts, sulfur, sulfuric acid, various metals, and other chemicals may result in fires or explosions, particularly if any solid materials are finely divided. Excessive heat, as in fires, may cause evolution of oxygen gas that may increase the intensity of fires and may also result in explosions. Mixtures with combustible materials are very flammable and may be ignited by friction. It is used for making herbicides, explosives, dyes, matches, inks, cosmetics, pharmaceuticals, defoliants, paper, and leather.

CAS Number: 7775-09-9
Molecular Formula: ClNaO3
Molecular Weight: 90.44 g/mol
Color / Form: Colorless cubic crystals
Melting Point: 478 °F (USCG, 1999)
Specific Gravity: 2.468 g/cu cm in crystalline form
Vapor Pressure: Negligible at room temperature
Water Solubility: Slightly soluble in methanol
Log P: -7.18 (estimated)
pH: Aqueous solution is neutral

Special Provisions

49 CFR 172.102 special provision codes for this entry: A9, IB8, IP2, IP4, N34, T3, TP33. These codes modify the general requirements (packaging, quantity limits, exceptions) for this specific material. Look up each code in 49 CFR 172.102 for the full text.

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Reference data compiled from the DOT Hazardous Materials Table (49 CFR 172.101), the 2024 Emergency Response Guidebook, and public chemical databases (PubChem, NIOSH, EPA). Always verify the correct shipping description against the current regulation and the manufacturer's SDS Section 14 before shipping.