UN/NA Number Reference

UN 1193: Ethyl methyl ketone (Mek)

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 1193 is assigned the proper shipping name Ethyl methyl ketone (Mek) in the U.S. DOT Hazardous Materials Table (49 CFR 172.101). It is classified as a Class 3 Flammable Liquid material, Packing Group II. 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

Methyl ethyl ketone appears as colorless fairly volatile liquid with a pleasant pungent odor. Flash point 20 °F. Vapors heavier than air. Does not react with water or many common materials. Stable in normal transportation. Irritates the nose, eyes, and throat. Combustion may produce toxic materials. Density 6.7 lb / gal. Used as a solvent, for making other chemicals, and for production of wax from petroleum.

CAS Number: 78-93-3

Molecular Formula: C4H8O

Molecular Weight: 72.11 g/mol

Color / Form: Colorless liquid

Odor: Acetone-like odor

Boiling Point: 175 F

Melting Point: -123.3 °F (NTP, 1992)

Flash Point: 26 F

Autoignition: 961 °F (USCG, 1999)

Specific Gravity: 0.806 (floats on water)

Vapor Pressure: 95 mmHg at 20 C (68 F) (vapor pressure at 20°C is 95 mmHg, which is a standard value for MEK at room temperature; note: the user asked for Fahrenheit, but vapor pressure is typically reported at 20°C, which is 68°F, so I'll include both for clarity but keep the primary unit as mmHg as requested),

Vapor Density: 2.42 (heavier than air)

Water Solubility: greater than or equal to 100 mg/mL at 66 °F (NTP, 1992)

Log P: log Kow = 0.29

Regulatory Data

CERCLA RQ (40 CFR 302.4)

5000 lb

OSHA PEL

200 590 200 ppm (ST) 300 ppm

NIOSH REL

TWA 200 ppm (590 mg/m 3 ) ST 300 ppm (885 mg/m 3 )

IDLH

3000 ppm

RCRA Waste Code(s)

[object Object], [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: IB2, T4, 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 1193 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.