UN/NA Number Reference
DOT Class 2.1 Flammable Gas placard

UN 3358: Refrigerating machines, containing flammable, non-toxic gas

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 3358 is assigned the proper shipping name Refrigerating machines, containing flammable, non-toxic gas in the U.S. DOT Hazardous Materials Table (49 CFR 172.101). It is classified as a Class 2.1 Flammable Gas material. Required label(s): 2.1.

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 115)

Hazards: Extremely flammable. May be ignited by heat, sparks, or flames. Vapors may travel to ignition source and flash back. Containers may rocket or BLEVE.

Fire: Do not extinguish unless flow can be stopped. Use water spray to cool containers. Move containers from fire if safe.

Spill: Eliminate ignition sources. Stop leak if safe. Use water spray to reduce vapors.

Need the full interactive record? Open UN 3358 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.