UN 1144 — Crotonylene
Placard: Flammable. ERG Guide 128. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1144 is Crotonylene, a flammable material assigned to ERG Guide 128. It may be encountered as a volatile liquid or liquefied material, so container markings and SDS should be checked before response actions.
Hazard overview: UN 1144 presents flammable vapor, pressure/container and flashback hazards. Vapors can form explosive mixtures with air and collect in low areas, while heated containers may fail or vent.
Response guidance: For a UN 1144 incident, responders should confirm the product using shipping papers, container markings, SDS and ERG Guide 128. Establish incident command, isolate the area, stay upwind and uphill, remove ignition sources when safe, keep vapors or runoff out of sewers and use compatible Class B fire-control agents from a protected position.
Firefighter training notes: Training for UN 1144 should emphasize flammable liquid vapor travel, flashback, sewer vapor explosion risk, foam compatibility, container cooling and atmospheric monitoring. Common errors include standing downwind, allowing runoff into drains and ignoring low-area vapor collection. Use ERG 128, SDS and local SOP.
Regulatory context: Crotonylene is regulated as a hazardous material for transportation and emergency response purposes. Transportation, workplace exposure, spill reporting, waste handling, storage and environmental requirements may vary by formulation, quantity and jurisdiction. Verify current requirements through shipping papers, SDS, facility documents and applicable DOT, OSHA, EPA, NFPA, state or local authority guidance.
Storage & handling: Crotonylene should be stored in tightly closed compatible containers in a cool, dry, well-ventilated flammable-liquid storage area. Keep away from heat, sparks, open flames, oxidizers and incompatible materials, with bonding/grounding, secondary containment and drain protection where required.
UN 1144 Quick Details
Common Hazards of UN 1144
- HIGHLY FLAMMABLE compressed or liquefied material; vapors may ignite easily.
- Vapors may form explosive mixtures with air and flash back to the source.
- Vapors are heavier than air and may spread into low or confined areas.
- Container heating may increase pressure and rupture risk.
- Fire may produce irritating or toxic combustion products.
- Released material may create a vapor cloud near the leak source.
- Use product markings and SDS to confirm gas/liquid state and container behavior.
Chemical Identity & Physical Properties
Colorless gas with a characteristic acetylene-like odor. Shipped as a liquefied compressed gas.
| Also known as | 2-ButyneDimethylacetyleneBut-2-yneDimethyl acetylene |
| CAS Number | 503-17-3 |
| Appearance | Colorless gas with a characteristic acetylene-like odor. Shipped as a liquefied compressed gas. |
| Flash Point | Not applicable (gas) |
| Boiling Point | 27C (81F) |
| Vapor Density | 1.9 (heavier than air) |
| Water Reactivity | No significant reaction with water |
Fireground Response Guidance — UN 1144
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for fire, heavy vapor or confined-space exposure. Chemical-resistant gloves, splash protection and protective clothing should be selected using SDS, product concentration and incident command.
Isolation & Evacuation
First Actions for a UN 1144 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.
- Eliminate ignition sources if it is safe to do so.
- Do not touch or walk through spilled liquid unless properly trained and wearing appropriate protective equipment.
- Ventilate closed spaces before entering, but only if properly trained, equipped and authorized by incident command.
- Isolate the spill or leak area for at least 50 meters (150 feet) in all directions.
- For large spills, fire involvement or strong vapor movement, expand isolation and consider downwind evacuation based on monitoring and incident command.
- Use ERG Guide 128, shipping papers, SDS and local SOP for protective actions and entry decisions.
📋 Copy & Share Field Card
UN 1144 — CrotonyleneUse 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.