UN 3159 — Tetrafluoroethane
Placard: Non-Flammable Gas. ERG Guide 126. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3159 is Tetrafluoroethane, a non-flammable liquefied refrigerant gas assigned to ERG Guide 126. Frostbite, asphyxiation and HF fire products are key concerns.
Hazard overview: Non-flammable liquefied refrigerant gas; pressure, asphyxiation and frostbite are primary hazards. Heavy vapor can collect in low or confined areas and displace oxygen. Liquefied gas contact can cause frostbite or cold burns.
Response guidance: For UN 3159, isolate the area, avoid exposure and use SCBA where vapor, gas, dust, smoke or fire is present. Verify exact contents with SDS, labels and ERG 126.
Firefighter training notes: Training for UN 3159 should emphasize product verification, SCBA use, exposure control, decontamination, runoff containment and SDS/shipping paper review. Use ERG 126, SDS and local SOP.
Regulatory context: Tetrafluoroethane is regulated as a hazardous material for transport and emergency response. Storage, reporting, exposure, waste and incident-notification duties depend on quantity, package type, formulation and jurisdiction; verify shipping papers, SDS and authority guidance.
Storage & handling: Tetrafluoroethane should be stored in tightly closed compatible containers or packages with ventilation, secondary containment, restricted access and SDS-based segregation from incompatible materials.
UN 3159 Quick Details
Common Hazards of UN 3159
- Non-flammable liquefied refrigerant gas; pressure, asphyxiation and frostbite are primary hazards.
- Heavy vapor can collect in low or confined areas and displace oxygen.
- Liquefied gas contact can cause frostbite or cold burns.
- Cylinders exposed to fire may vent, rupture or rocket.
- Fire or hot surfaces may decompose the gas and produce hydrogen fluoride and other toxic/corrosive fluorinated products.
- Vapor exposure may cause dizziness or cardiac sensitization under high concentrations.
- Ventilation and monitoring are important in enclosed areas.
Chemical Identity & Physical Properties
Colorless, odorless liquefied gas. Shipped as a liquefied compressed gas under its own vapor pressure.
| Also known as | R-134aHFC-134aNorfluraneFreon 134aTetrafluoroethane |
| CAS Number | 811-97-2 |
| Appearance | Colorless, odorless liquefied gas. Shipped as a liquefied compressed gas under its own vapor pressure. |
| Flash Point | Not applicable (non-flammable gas) |
| Boiling Point | -26C (-15F) |
| Vapor Density | 3.6 (heavier than air) |
| Water Reactivity | No significant reaction; low water solubility |
Fireground Response Guidance — UN 3159
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for releases, fire or confined spaces. Wear eye/face protection and insulated gloves where liquefied or cryogenic gas contact is possible.
Isolation & Evacuation
First Actions for a UN 3159 Incident
- Call 911 and the emergency response number on the shipping paper, if available.
- Keep unauthorized personnel away and establish incident command.
- Stay upwind, uphill and upstream.
- Avoid breathing vapor, gas, dust, mist, smoke or fumes and avoid skin or eye contact.
- Do not touch damaged containers, cylinders, articles or spilled material without proper training and PPE.
- Prevent contaminated runoff, debris and decontamination waste from spreading.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 126, SDS, shipping papers, markings and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 3159 — TetrafluoroethaneUse 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.