UN 2283: Isobutyl methacrylate, stabilized

DOT Classification and Shipping

UN 2283 is assigned the proper shipping name Isobutyl methacrylate, stabilized in the U.S. DOT Hazardous Materials Table (49 CFR 172.101). It is classified as a Class 3 Flammable Liquid material, Packing Group III. Required label(s): 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 127)

Hazards: HIGHLY FLAMMABLE. Vapors may form explosive mixtures with air. Vapors heavier than air, travel to ignition source and flash back. Runoff may cause fire/explosion.

Fire: Small: dry chemical, CO2, water spray or alcohol-resistant foam. Large: water spray, fog or alcohol-resistant foam. Do not use straight streams. Cool tanks with water.

Spill: Eliminate ignition sources. Ground equipment. Stop leak if safe. Use vapor-suppressing foam. Absorb with earth/sand. Dike large spills. Water spray may reduce vapor.

Chemical and Physical Properties

Isobutyl methacrylate is a colorless liquid with a flash point of 120 °F. When heated to high temperatures it may release acrid smoke and fumes. If it is subjected to heat for prolonged periods or becomes contaminated, it is subject to polymerization. If the polymerization takes place inside a container, the container may violently rupture. The vapors are heavier than air. It may be irritating to skin and eyes and produce a narcotic effect. It is used in making acrylic resins.

Special Provisions

49 CFR 172.102 special provision codes for this entry: 387, B1, IB3, T2, TP1. 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 2283 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.