UN 2279 — Hexachlorobutadiene
Placard: Toxic. ERG Guide 151. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2279 is Hexachlorobutadiene, a highly toxic chlorinated liquid assigned to ERG Guide 151. It can sink in water and create persistent toxic contamination.
Hazard overview: HIGHLY TOXIC chlorinated liquid; may be fatal if inhaled, ingested or absorbed through skin. Avoid all skin contact; contaminated clothing can extend exposure. Non-combustible or not readily combustible, but heating can produce toxic/corrosive decomposition gases.
Response guidance: For a UN 2279 incident, verify the product with shipping papers, container markings, SDS and ERG Guide 151. Establish incident command, isolate the area, stay upwind, control ignition or incompatibility hazards, prevent runoff, dust or vapor spread and base entry/fire-control actions on monitoring and local SOP.
Firefighter training notes: Training for UN 2279 should emphasize toxic skin/vapor exposure, contaminated clothing, toxic fire products, decontamination waste and runoff containment. Use ERG 151, SDS and local SOP.
Regulatory context: Hexachlorobutadiene is regulated as a hazardous material for transportation and emergency response purposes. Storage, workplace exposure, emergency planning, spill reporting, waste handling and environmental requirements vary by exact product, concentration, quantity and jurisdiction. Verify current requirements through shipping papers, SDS, container markings and applicable DOT, OSHA, EPA, NFPA, state or local authority guidance.
Storage & handling: Hexachlorobutadiene should be stored in tightly closed compatible containers in a secure toxic/corrosive-material area with secondary containment, restricted access, ventilation and waste/decontamination planning according to SDS.
UN 2279 Quick Details
Common Hazards of UN 2279
- HIGHLY TOXIC chlorinated liquid; may be fatal if inhaled, ingested or absorbed through skin.
- Avoid all skin contact; contaminated clothing can extend exposure.
- Non-combustible or not readily combustible, but heating can produce toxic/corrosive decomposition gases.
- Liquid is denser than water and may sink, spreading contamination below the surface.
- Fire may produce hydrogen chloride, phosgene-type gases and other toxic chlorinated smoke.
- Runoff may pollute waterways and create persistent contamination.
- Containers may rupture or fail when heated.
Chemical Identity & Physical Properties
Colorless to pale yellow liquid with a mild turpentine-like odor. Insoluble in water and denser than water.
| Also known as | HCBDPerchlorobutadiene1,1,2,3,4,4-Hexachloro-1,3-butadieneDolen-purGP-40-66:120 |
| CAS Number | 87-68-3 |
| Appearance | Colorless to pale yellow liquid with a mild turpentine-like odor. Insoluble in water and denser than water. |
| Flash Point | 95°C (203°F) |
| Boiling Point | 215°C (419°F) |
| Vapor Density | 9.0 (much heavier than air) |
| Water Reactivity | No significant reaction with water; insoluble and will sink |
Fireground Response Guidance — UN 2279
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for vapor, mist, fire or confined-space exposure. Wear chemical-resistant gloves, boots, eye/face protection and protective clothing selected from SDS; avoid all skin contact.
Isolation & Evacuation
First Actions for a UN 2279 Incident
- CALL 911. Then call the emergency response telephone number on the shipping paper, if available.
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Avoid breathing vapors, dust, mist, smoke or fumes and avoid skin or eye contact.
- Do not touch damaged containers or spilled material unless properly trained and wearing appropriate protective equipment.
- Prevent contaminated liquid, residues, runoff and decontamination waste from spreading.
- Ventilate closed spaces before entering, but only if properly trained, equipped, monitored and authorized by incident command.
- Isolate the spill or release area and expand the perimeter for fire involvement, vapor spread, dust generation, water reaction or unknown product identity.
- Use ERG Guide 151, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 2279 — HexachlorobutadieneUse for: Quick radio or face-to-face size-up. Short, structured, field-ready.
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief.
Use for: Quick text to command or incoming units. Fits in a single SMS.