UN 2453 — Refrigerant gas R-161
Placard: Flammable Gas. ERG Guide 115. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2453 is Refrigerant gas R-161, a flammable liquefied refrigerant gas assigned to ERG Guide 115. Flashback, frostbite and cylinder rupture are key concerns.
Hazard overview: EXTREMELY FLAMMABLE liquefied compressed refrigerant gas; may ignite easily by heat, sparks or flames. Gas can form explosive mixtures with air and flash back from ignition sources. Liquefied gas can cause frostbite and cold burns.
Response guidance: For UN 2453, isolate the leak, eliminate ignition sources and use SCBA. Stop gas flow only if safe; do not extinguish a leaking gas fire unless flow can be stopped, and cool cylinders from protection using ERG 115.
Firefighter training notes: Training for UN 2453 should emphasize flammable gas behavior, source isolation, no-extinguishment-until-flow-stopped tactics, cylinder cooling, flashback and frostbite. Use ERG 115, SDS and local SOP.
Regulatory context: Refrigerant gas R-161 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-161 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 2453 Quick Details
Common Hazards of UN 2453
- EXTREMELY FLAMMABLE liquefied compressed refrigerant gas; may ignite easily by heat, sparks or flames.
- Gas can form explosive mixtures with air and flash back from ignition sources.
- Liquefied gas can cause frostbite and cold burns.
- Gas is heavier than air and may collect in low or confined areas.
- Cylinders exposed to fire may vent, rupture or rocket.
- Fire or hot surfaces may decompose refrigerant and produce toxic/corrosive fluoride gases.
- Do not extinguish a leaking gas fire unless the gas flow can be stopped safely.
Chemical Identity & Physical Properties
Colorless, liquefied compressed gas with a faint ethereal odor. Shipped as a liquefied gas under pressure.
| Also known as | Ethyl fluorideFluoroethaneMonofluoroethaneHFC-161R-161 |
| CAS Number | 353-36-6 |
| Appearance | Colorless, liquefied compressed gas with a faint ethereal odor. Shipped as a liquefied gas under pressure. |
| Flash Point | -50C (-58F) |
| Boiling Point | -37C (-35F) |
| Vapor Density | 1.7 (heavier than air) |
| Water Reactivity | No significant reaction with water |
Fireground Response Guidance — UN 2453
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for gas, fire or confined-space exposure. Wear flame/chemical protection as appropriate and insulated gloves for liquefied-gas frostbite risk.
Isolation & Evacuation
First Actions for a UN 2453 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.
- Eliminate ignition sources if safe and do not extinguish a leaking gas fire unless flow can be stopped.
- Avoid breathing vapor, dust, gas, mist, smoke or fumes and avoid skin or eye contact.
- Do not touch damaged containers or spilled material without proper training and PPE.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 115, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 2453 — Refrigerant gas R-161Use 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.