UN/NA Number Reference
DOT Class 2.1 Flammable Gas placard

UN 1063: Methyl chloride

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 1063 is assigned the proper shipping name Methyl chloride 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.

Chemical and Physical Properties

Methyl chloride appears as a colorless gas with a faint sweet odor. Shipped as a liquid under its vapor pressure. A leak may either be liquid or vapor. Contact with the liquid may cause frostbite by evaporative cooling. Easily ignited. Vapors heavier than air. Can asphyxiate by the displacement of air. Under prolonged exposure to fire or intense heat the containers may rupture violently and rocket. Used to make other chemicals and as a herbicide.

CAS Number: 74-87-3
Molecular Formula: CH3Cl
Molecular Weight: 50.49 g/mol
Color / Form: Colorless compressed gas or liquid
Odor: Faint sweet ethereal odor
Boiling Point: -11.6 F
Melting Point: -143 °F (NTP, 1992)
Flash Point: -49.9 F
Autoignition: 1170 °F (USCG, 1999)
Specific Gravity: 0.997 at -11.2 F
Vapor Pressure: 760 mmHg at -11 F
Vapor Density: 1.8 (heavier than air)
Water Solubility: Slightly soluble
Log P: log Kow = 0.91

Regulatory Data

CERCLA RQ (40 CFR 302.4)
100 lb
OSHA PEL
TWA 100 ppm C 200 ppm 300 ppm (5-minute maximum peak in any 3 hours)
NIOSH REL
Ca
IDLH
Ca [2000 ppm]
RCRA Waste Code(s)
[object Object]

A release of this material at or above its CERCLA reportable quantity (100 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: N86, T50. 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 1063 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.