UN/NA Number Reference

DOT Class 4.3 Dangerous When Wet placard

UN 1426: Sodium borohydride

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 1426 is assigned the proper shipping name Sodium borohydride in the U.S. DOT Hazardous Materials Table (49 CFR 172.101). It is classified as a Class 4.3 Dangerous When Wet material, Packing Group I. Required label(s): 4.3.

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 138)

Hazards: Corrosive. Reacts with water, produces corrosive/toxic gases. May ignite on water contact.

Fire: DO NOT use water. Use dry chemical, dry sand, soda ash.

Spill: Do not touch. Keep dry. Move from water source. Cover with dry earth.

Chemical and Physical Properties

Sodium borohydride is a white to grayish crystalline powder. It is decomposed by water to form sodium hydroxide, a corrosive material, and hydrogen, a flammable gas. The heat of this reaction may be sufficient to ignite the hydrogen. The material itself is easily ignited and burns vigorously once ignited. It is used to make other chemicals, treat waste water, and for many other uses.

CAS Number: 16940-66-2

Molecular Formula: BH4Na

Molecular Weight: 37.84 g/mol

Color / Form: White to gray-white microcystalline powder or lumps

Melting Point: >400 °C (vacuum) (decomposes)

Autoignition: ~220 °C

Specific Gravity: 1.074 (sinks in water)

Water Solubility: Soluble in "Cellosolve" ether

Special Provisions

49 CFR 172.102 special provision codes for this entry: N40, W31. 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.

Need the full interactive record? Open UN 1426 in the SpillNerd lookup tool for the live database entry with placard graphics, GHS pictograms, full segregation tables, and synonym search. For another material, use the UN number and chemical lookup.

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.