UN/NA Number Reference
DOT Class 3 Flammable Liquid placard

UN 1237: Methyl butyrate

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 1237 is assigned the proper shipping name Methyl butyrate 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 129)

Hazards: Flammable. Irritating vapor. May cause dizziness. Toxic if inhaled or absorbed through skin.

Fire: Alcohol-resistant foam, dry chemical, CO2, water spray.

Spill: Eliminate ignition sources. Ventilate area. Absorb with earth or sand.

Chemical and Physical Properties

Methyl butyrate appears as a clear colorless liquid. Flash point 57 °F. Less dense than water and slightly soluble in water. Hence floats on water. Vapors heavier than air.

CAS Number: 623-42-7
Molecular Formula: C5H10O2
Molecular Weight: 102.13 g/mol
Color / Form: Colorless liquid
Odor: APPLE-LIKE ODOR
Boiling Point: 216 F
Melting Point: -139 °F (NTP, 1992)
Flash Point: 57 F
Specific Gravity: 0.8984 (floats on water)
Vapor Pressure: 0.84 mmHg at 68 F
Vapor Density: 3.53 (heavier than air)
Water Solubility: 10 to 50 mg/mL at 72 F
Log P: log Kow= 1.29

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 1237 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.