UN/NA Number Reference
DOT Class 3 Flammable Liquid placard

UN 1918: Isopropylbenzene (cumene)

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 1918 is assigned the proper shipping name Isopropylbenzene (cumene) 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 130)

Hazards: Flammable. Toxic vapor. Harmful if inhaled or absorbed. May accumulate in low areas.

Fire: Dry chemical, CO2, foam, water spray. Do not use straight streams.

Spill: Eliminate ignition sources. Stop leak. Absorb with sand/earth. Prevent waterway contamination.

Chemical and Physical Properties

Cumene appears as a clear colorless liquid with an aromatic odor. Less dense than water and insoluble in water. Vapors heavier than air. May be moderately toxic by inhalation, ingestion and skin absorption.

CAS Number: 98-82-8
Molecular Formula: C9H12
Molecular Weight: 120.19 g/mol
Color / Form: Colorless liquid
Odor: Gasoline-like odor
Boiling Point: 306 F
Melting Point: -140.9 °F (USCG, 1999)
Flash Point: 96 F
Autoignition: 797 °F (USCG, 1999)
Specific Gravity: 0.866
Vapor Pressure: 25.85 mmHg
Vapor Density: 4.1 (heavier than air)
Water Solubility: Insoluble in water
Log P: log Kow = 3.66

Regulatory Data

CERCLA RQ (40 CFR 302.4)
5000 lb
OSHA PEL
TWA 50 ppm (245 mg/m 3 ) [skin]
NIOSH REL
TWA 50 ppm (245 mg/m 3 ) [skin]
IDLH
900 ppm [10%LEL]
RCRA Waste Code(s)
[object Object]

A release of this material at or above its CERCLA reportable quantity (5000 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: 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 1918 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.