UN 1046: Helium, compressed

DOT Classification and Shipping

UN 1046 is assigned the proper shipping name Helium, compressed in the U.S. DOT Hazardous Materials Table (49 CFR 172.101). It is classified as a Class 2.2 Non-Flammable Gas material. Required label(s): 2.2.

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 121)

Hazards: May cause asphyxiation in confined areas. Rapid expansion may cause frostbite. Containers may BLEVE.

Fire: Use agent for surrounding fire. Cool containers with water from distance.

Spill: Ventilate area. Do not touch liquid. Stop leak if safe.

Chemical and Physical Properties

Helium appears as a colorless, odorless, noncombustible gas. Can asphyxiate. Inhalation causes the voice to become squeaky (Mickey Mouse voice). Exposure of the container to prolonged heat or fire can cause it to rupture violently and rocket. If liquefied, contact of the very cold liquid with water causes violent boiling. Pressures may build to dangerous levels if the liquid contacts water in a closed container. Used in arc welding, to trace leaks in refrigeration and other closed systems and as a lifting gas for lighter-than-air aircraft.

Need the full interactive record? Open UN 1046 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.