UN/NA Number Reference
DOT Class 8 Corrosive placard

UN 2218: Acrylic acid, stabilized

49 CFR 172.101 Hazardous Materials Table·ERG 2024

DOT Classification and Shipping

UN 2218 is assigned the proper shipping name Acrylic acid, stabilized in the U.S. DOT Hazardous Materials Table (49 CFR 172.101). It is classified as a Class 8 Corrosive material, Packing Group II. Required label(s): 8, 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 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

Acrylic acid is a colorless liquid with a distinctive acrid odor. Flash point 130 °F. Boiling point 286 °F. Freezing point 53 °F. Corrosive to metals and tissue. Prolonged exposure to fire or heat can cause polymerization. If polymerization takes place in a closed container, violent rupture may occur. The inhibitor (usually hydroquinone) greatly reduces the tendency to polymerize.

CAS Number: 79-10-7
Molecular Formula: C3H4O2
Molecular Weight: 72.06 g/mol
Color / Form: Acrid liquid
Odor: Acrid odor and fumes
Boiling Point: 286 F
Melting Point: 55 °F (NTP, 1992)
Flash Point: 130 F
Autoignition: 820 °F (USCG, 1999)
Specific Gravity: 1.0497
Vapor Pressure: 3.2 mmHg
Vapor Density: 2.5 (heavier than air)
Water Solubility: greater than or equal to 100 mg/mL at 63 °F (NTP, 1992)
Log P: 0.35

Regulatory Data

CERCLA RQ (40 CFR 302.4)
5000 lb
OSHA PEL
none
NIOSH REL
TWA 2 ppm (6 mg/m 3 ) [skin]
IDLH
N
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: 387, B2, IB2, T7, 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 2218 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.