UN 2850 — Propylene tetramer
Placard: Flammable. ERG Guide 128. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
Propylene tetramer is a flammable C12 olefin mixture shipped as a clear to pale yellow hydrocarbon liquid. Its main emergency concern is mobile vapor that can ignite or flash back.
Hazard overview: The liquid is not water-reactive, but it floats and can spread fire on water. Vapors are heavier than air, may collect in low areas, and can reach ignition sources before responders see the liquid.
Response guidance: Eliminate ignition sources, keep personnel out of vapor paths, and isolate drains or low points. Use foam, dry chemical, or CO2 for fire attack and cool exposed containers from a protected position.
Firefighter training notes: Training should emphasize ignition-source control, vapor monitoring, drain protection, foam selection, and container cooling for UN 2850.
Regulatory context: Use the UN number, proper shipping name, hazard class, packing details, SDS, and ERG 128 as the initial regulatory reference set.
Storage & handling: Store in approved flammable or combustible liquid containers away from ignition sources, oxidizers, heat, and incompatible materials; maintain ventilation and bonding/grounding where required.
UN 2850 Quick Details
Common Hazards of UN 2850
- Flammable hydrocarbon liquid; heat, sparks, static, or flame can ignite vapors.
- Vapors can form explosive mixtures with air and may flash back from distant ignition sources.
- Heavier-than-air vapors can move along floors, ditches, and sewers.
- Runoff to drains or waterways can spread fire and create vapor explosion hazards.
- Containers may rupture or explode when heated by fire.
- Burning material can produce irritating smoke and carbon oxides.
- Liquid floats on water and may spread over a larger surface area.
Chemical Identity & Physical Properties
Clear to pale yellow liquid with mild petroleum odor. Liquid at room temperature with low viscosity
| Also known as | TetrapropyleneDodecenePropene tetramerC12 olefin |
| CAS Number | 6842-15-5 |
| Appearance | Clear to pale yellow liquid with mild petroleum odor. Liquid at room temperature with low viscosity. |
| Flash Point | 40°C (104°F) |
| Boiling Point | 175-210°C (347-410°F) |
| Vapor Density | 5.8 (heavier than air) |
| Water Reactivity | No significant reaction; immiscible and floats on water |
Fireground Response Guidance — UN 2850
Extinguishing Media
PPE Requirements
Use SCBA in vapor areas, confined spaces, or fire conditions. Chemical-resistant gloves, splash protection, and flame-resistant outer protection are appropriate for spill work.
Isolation & Evacuation
First Actions for a UN 2850 Incident
- Call 911 and the emergency response number on shipping papers or the SDS.
- Keep unauthorized personnel away and remove ignition sources if this can be done safely.
- Stay upwind, uphill, and upstream; vapors may collect in low areas and drains.
- Avoid breathing vapor and avoid skin or eye contact with liquid or contaminated runoff.
- Do not touch damaged containers or enter vapor areas without SCBA and chemical PPE.
- Ventilate confined spaces only if trained, equipped, and monitoring for flammable vapor.
- Use ERG guidance, SDS, shipping papers, and vapor monitoring before selecting tactics.
📋 Copy & Share Field Card
UN 2850 — Propylene tetramerUse 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.