UN/NA Number Reference
DOT Class 5.1 Oxidizer placard

UN 1476: Magnesium peroxide

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 1476 is assigned the proper shipping name Magnesium peroxide 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 144)

Hazards: Oxidizer. Reacts with water. May produce toxic or corrosive solutions.

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

Spill: Keep material dry. Keep combustibles away.

Chemical and Physical Properties

Magnesium peroxide appears as a white powder. Noncombustible but accelerates the burning of combustible material, if the combustible material is finely divided the mixture may be explosive. Mixtures of combustible material and the peroxide can be ignited by friction or contact with moisture. Used in medicine, and as a bleaching agent.

CAS Number: 7778-50-9
Molecular Formula: MgO2
Molecular Weight: 56.304 g/mol
Color / Form: White cubic crystals
Odor: Odorless
Boiling Point: Decomposes at 932 °F (NTP, 1992)
Melting Point: 100 °C (decomposes)
Autoignition: Not flammable (USCG, 1999)
Specific Gravity: Approximately 3.0 g/cu cm
Water Solubility: Soluble in dilute acid solutions with formation of hydrogen peroxide
pH: Acid reaction: a 1% aqueous solution has pH of 4.04 and a 10% solution has a pH of 3.57

Regulatory Data

CERCLA RQ (40 CFR 302.4)
10 lb

A release of this material at or above its CERCLA reportable quantity (10 lb) requires immediate notification to the National Response Center at 800-424-8802.

Special Provisions

49 CFR 172.102 special provision codes for this entry: IB6, IP2, T3, TP33, W100. 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.