UN 2424 — Refrigerant gas R-218
Placard: Non-Flammable Gas. ERG Guide 126. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2424 is Refrigerant gas R-218, a non-flammable liquefied refrigerant gas assigned to ERG Guide 126. Oxygen displacement, frostbite and toxic decomposition are key hazards.
Hazard overview: NON-FLAMMABLE liquefied compressed refrigerant gas; pressure and asphyxiation hazards are primary. Heavy gas can collect in low or confined areas and displace oxygen without warning. Contact with liquefied gas can cause frostbite or cold burns.
Response guidance: For UN 2424, isolate low areas, ventilate only after monitoring and check oxygen levels. Protect against frostbite, cool cylinders from a distance and verify decomposition hazards with SDS and ERG 126.
Firefighter training notes: Training for UN 2424 should emphasize asphyxiation, oxygen monitoring, low-area accumulation, frostbite, cylinder heating and toxic decomposition products in fire. Use ERG 126, SDS and local SOP.
Regulatory context: Refrigerant gas R-218 is regulated as a hazardous material for transport and emergency response. Storage, exposure, spill reporting, waste and fire-code duties depend on quantity, concentration and jurisdiction; verify shipping papers, SDS and local authority requirements.
Storage & handling: Refrigerant gas R-218 cylinders should be secured in a cool, ventilated gas-storage area away from heat, physical damage and incompatible materials. Provide leak detection, ventilation and emergency planning according to SDS and local code.
UN 2424 Quick Details
Common Hazards of UN 2424
- NON-FLAMMABLE liquefied compressed refrigerant gas; pressure and asphyxiation hazards are primary.
- Heavy gas can collect in low or confined areas and displace oxygen without warning.
- Contact with liquefied gas can cause frostbite or cold burns.
- Containers exposed to fire may vent, rupture or rocket.
- Fire or hot surfaces may decompose refrigerant and produce toxic/corrosive fluoride gases.
- Ventilation and oxygen monitoring are critical in enclosed areas.
- Exact gas identity and decomposition hazards should be verified from SDS and cylinder markings.
Chemical Identity & Physical Properties
Colorless, odorless liquefied compressed gas. Heavier than air. Non-flammable.
| Also known as | OctafluoropropanePerfluoropropaneR-218PFC-218Freon 218FC-218 |
| CAS Number | 76-19-7 |
| Appearance | Colorless, odorless liquefied compressed gas. Heavier than air. Non-flammable. |
| Flash Point | Not applicable (non-flammable gas) |
| Boiling Point | -37C (-35F) |
| Vapor Density | 7.6 (much heavier than air) |
| Water Reactivity | No significant reaction with water |
Fireground Response Guidance — UN 2424
Extinguishing Media
PPE Requirements
Use SCBA and oxygen monitoring in confined or oxygen-deficient areas. Wear face/eye protection and insulated gloves for liquefied gas or cold vapor contact.
Isolation & Evacuation
First Actions for a UN 2424 Incident
- Call 911 and the emergency response number on the shipping paper, if available.
- Keep unauthorized personnel away and establish incident command.
- Stay upwind and keep people out of low or poorly ventilated areas.
- Treat the release as an inhalation hazard until monitoring proves otherwise.
- Do not touch leaking cylinders or liquefied gas without proper training and PPE.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 126, SDS, cylinder markings and air monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 2424 — Refrigerant gas R-218Use 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.