UN/NA Number Reference
DOT Class 8 Corrosive placard

UN 2576: Phosphorus oxybromide, molten

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 2576 is assigned the proper shipping name Phosphorus oxybromide, molten in the U.S. DOT Hazardous Materials Table (49 CFR 172.101). It is classified as a Class 8 Corrosive material, Packing Group II. Required label(s): 8.

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 137)

Hazards: Produce flammable gases on contact with water. May ignite on contact with water. Some react violently with water.

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

Spill: Do not touch. Keep material dry. Move containers from water. Dike to prevent water contact.

Chemical and Physical Properties

Phosphorus oxybromide appears as a colorless crystalline solid or liquid if heated above 133 °F with a pungent odor. It is commonly heated and shipped in a molten state. Soluble in water, but, decomposed by water to hydrobromic and phosphoric acid with evolution of heat. Reacts with organic materials to cause fire. Evolves highly toxic and corrosive gases when exposed to fire. Corrosive to metals and tissue. Used to make other chemicals.

CAS Number: 7789-59-5
Molecular Formula: Br3OP
Molecular Weight: 286.69 g/mol
Color / Form: COLORLESS CRYSTALS
Boiling Point: AT 758 MM HG IT BOILS AT 193 C WITH DECOMPOSITION
Melting Point: 133 °F (NOAA, 2007)
Specific Gravity: greater than 1
Water Solubility: SOL IN ETHER, BENZENE, CHLOROFORM, CARBON DISULFIDE, CONCENTRATED SULFURIC ACID

Special Provisions

49 CFR 172.102 special provision codes for this entry: B2, B8, IB1, N41, N43, T7, TP3, TP13. 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 2576 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.