UN/NA Number Reference
DOT Class 3 Flammable Liquid placard

UN 2054: Morpholine

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 2054 is assigned the proper shipping name Morpholine in the U.S. DOT Hazardous Materials Table (49 CFR 172.101). It is classified as a Class 3 Flammable Liquid material, Packing Group I. Required label(s): 3, 8.

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 132)

Hazards: HIGHLY FLAMMABLE. CORROSIVE. Causes burns. Vapors may form explosive mixture with air.

Fire: Alcohol-resistant foam, dry chemical, CO2. Do not use water jet. Cool containers.

Spill: Eliminate ignition sources. Do not touch. Stop leak if safe. Use foam.

Chemical and Physical Properties

Morpholine appears as a colorless liquid with a fishlike odor. Flash point 100 °F. Corrosive to tissue. Less dense than water and soluble in water. Vapors heavier than air. Used to make other chemicals, as a corrosion inhibitor, and in detergents.

CAS Number: 110-91-8
Molecular Formula: C4H9NO
Molecular Weight: 87.12 g/mol
Color / Form: Colorless liquid
Odor: Characteristic amine
Boiling Point: 264 F
Melting Point: 23.2 °F (NTP, 1992)
Flash Point: 100 F
Autoignition: 590 °F (USCG, 1999)
Specific Gravity: 1
Vapor Pressure: 6.6 mmHg at 68 F
Vapor Density: 3 (heavier than air)
Water Solubility: Soluble
Log P: log Kow = -0.86
pH: Strong base

Regulatory Data

OSHA PEL
TWA 20 ppm (70 mg/m 3 ) [skin]
NIOSH REL
TWA 20 ppm (70 mg/m 3 ) ST 30 ppm (105 mg/m 3 ) [skin]
IDLH
1400 ppm [10%LEL]

Special Provisions

49 CFR 172.102 special provision codes for this entry: T10, TP2. 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 2054 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.