UN 2451 — Nitrogen trifluoride
Placard: Non-Flammable Gas. ERG Guide 122. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2451 is Nitrogen trifluoride, a non-flammable oxidizing gas assigned to ERG Guide 122. It supports combustion and can produce fluoride gases in fire.
Hazard overview: NON-FLAMMABLE oxidizing compressed gas; supports combustion and can intensify fire. May react dangerously with fuels, oils, reducing agents or other oxidizable materials. Liquefied gas contact can cause frostbite or cold burns.
Response guidance: For UN 2451, isolate the gas release, keep combustibles away and use SCBA. Cool cylinders from protection, monitor low areas and verify oxidizer controls with SDS and ERG 122.
Firefighter training notes: Training for UN 2451 should emphasize exposure routes, SCBA use, vapor/dust monitoring, fire behavior, decontamination, runoff containment and SDS verification. Use ERG 122, SDS and local SOP.
Regulatory context: Nitrogen trifluoride 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: Nitrogen trifluoride 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 2451 Quick Details
Common Hazards of UN 2451
- NON-FLAMMABLE oxidizing compressed gas; supports combustion and can intensify fire.
- May react dangerously with fuels, oils, reducing agents or other oxidizable materials.
- Liquefied gas contact can cause frostbite or cold burns.
- Gas is heavier than air and may collect in low or confined areas.
- Fire or strong heat may produce toxic/corrosive fluoride gases.
- Cylinders exposed to fire may vent, rupture or rocket.
- Oxygen displacement is possible in enclosed or poorly ventilated spaces.
Chemical Identity & Physical Properties
Colorless, odorless compressed gas. Non-flammable but acts as a strong oxidizer. Shipped as a liquefied compressed gas under high pressure.
| Also known as | NF3Nitrogen fluorideTrifluoroaminePerfluoroammonia |
| CAS Number | 7783-54-2 |
| Appearance | Colorless, odorless compressed gas. Non-flammable but acts as a strong oxidizer. Shipped as a liquefied compressed gas under high pressure. |
| Flash Point | Not applicable (non-flammable gas) |
| Boiling Point | -129C (-200F) |
| Vapor Density | 2.5 (heavier than air) |
| Water Reactivity | Reacts slowly with water producing toxic and corrosive hydrogen fluoride gas |
Fireground Response Guidance — UN 2451
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 2451 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, 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 122, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 2451 — Nitrogen trifluorideUse 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.