UN 2447 — Phosphorus, white, molten
Placard: Spontaneously Combustible. ERG Guide 136. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2447 is Phosphorus, white, molten, a pyrophoric molten phosphorus entry assigned to ERG Guide 136. Air exposure, re-ignition and severe burn contamination are key hazards.
Hazard overview: PYROPHORIC molten white/yellow phosphorus; ignites spontaneously when exposed to air. Burning material produces dense white phosphorus oxide fumes that are irritating, corrosive and toxic. Molten material causes severe thermal and chemical burns and may continue burning in tissue or on surfaces.
Response guidance: For UN 2447, isolate the area, stay upwind and use SCBA with specialist hazmat controls. Keep incompatible water/moisture tactics under incident command, use compatible dry or directed agents and watch for re-ignition.
Firefighter training notes: Training for UN 2447 should emphasize reactivity, moisture control, compatible extinguishing media, re-ignition checks, SCBA use, decontamination and runoff control. Use ERG 136, SDS and local SOP.
Regulatory context: Phosphorus, white, molten 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: Phosphorus, white, molten should be stored under the SDS-specified protective medium/temperature control, away from heat, oxidizers and air exposure. Maintain containment for contaminated water or residues.
UN 2447 Quick Details
Common Hazards of UN 2447
- PYROPHORIC molten white/yellow phosphorus; ignites spontaneously when exposed to air.
- Burning material produces dense white phosphorus oxide fumes that are irritating, corrosive and toxic.
- Molten material causes severe thermal and chemical burns and may continue burning in tissue or on surfaces.
- May re-ignite after apparent extinguishment if exposed to air.
- Containers may rupture or explode when heated.
- Runoff or residues may spread toxic phosphorus contamination.
- Keep unburned material wet/submerged when directed by specialists, while controlling contaminated water.
Chemical Identity & Physical Properties
Translucent white to yellow waxy solid that becomes a colorless to yellow liquid when molten (above 44°C/111°F). Garlic-like odor. Pyrophoric material that ignites spontaneously in air.
| Also known as | White phosphorus moltenYellow phosphorus moltenP4 moltenTetraphosphorus molten |
| CAS Number | 12185-10-3 |
| Appearance | Translucent white to yellow waxy solid that becomes a colorless to yellow liquid when molten (above 44°C/111°F). Garlic-like odor. Pyrophoric material that ignites spontaneously in air. |
| Flash Point | Not applicable (pyrophoric solid/liquid, ignites spontaneously in air at approximately 30°C/86°F) |
| Boiling Point | 280°C (536°F) |
| Vapor Density | 4.3 (heavier than air) |
| Water Reactivity | No significant reaction with water, but hydrolyzes slowly forming phosphine gas and phosphoric acid |
Fireground Response Guidance — UN 2447
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA and fully encapsulating chemical protective clothing for close entry or unknown concentrations. Protect against severe chemical, thermal and eye exposure.
Isolation & Evacuation
First Actions for a UN 2447 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.
- Keep incompatible water or moisture controls strictly under incident command because reaction or re-ignition hazards are severe.
- 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 136, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 2447 — Phosphorus, white, moltenUse 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.