UN 1338 — Phosphorus, amorphous
Placard: Flammable Solid. ERG Guide 133. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1338 is Phosphorus, amorphous, a Class 4 flammable solid assigned to ERG Guide 133. It may burn as powder, granules, lumps or softened material depending on the exact product and fire conditions.
Hazard overview: UN 1338 presents flammable solid, dust and smoke hazards. Powders can burn rapidly or form dust-air mixtures, while fire may produce irritating smoke and contaminated residue.
Response guidance: For a UN 1338 incident, responders should verify the product with shipping papers, package markings, SDS and ERG Guide 133. Establish incident command, isolate the area, stay upwind, avoid unnecessary disturbance of powder or damaged packaging, and use only extinguishing agents compatible with the specific material.
Firefighter training notes: Training for UN 1338 should emphasize dust fire behavior, rapid surface burning, smoke exposure, compatible extinguishment and avoiding dust cloud generation. Use ERG 133, SDS and local SOP.
Regulatory context: Phosphorus, amorphous is regulated as a hazardous material for transportation and emergency response purposes. Transportation, workplace exposure, spill reporting, waste handling, storage and environmental requirements may vary by formulation, quantity and jurisdiction. Verify current requirements through shipping papers, SDS, facility documents and applicable DOT, OSHA, EPA, NFPA, state or local authority guidance.
Storage & handling: Phosphorus, amorphous should be stored in compatible containers in a cool, dry, well-ventilated area away from heat, sparks, open flames, oxidizers and incompatible materials. Prevent dust release, friction, impact and unauthorized access.
UN 1338 Quick Details
Common Hazards of UN 1338
- FLAMMABLE/COMBUSTIBLE organic solid; may be ignited by heat, sparks, friction or flames.
- Powder or dust may burn rapidly and may form an explosive dust-air mixture.
- Fire may produce irritating or toxic smoke.
- Some material may soften, melt or flow when heated, spreading the fire.
- Containers or bags may fail when exposed to fire.
- Runoff from fire control may carry contaminated residue.
- Avoid creating dust clouds during cleanup.
Chemical Identity & Physical Properties
Reddish-brown to violet powder or crystalline solid with no distinct odor. Non-volatile at room temperature and less reactive than white phosphorus.
| Also known as | Red phosphorusViolet phosphorusHittorf's phosphorusPhosphorus rougeAmorphous red phosphorus |
| CAS Number | 7723-14-0 |
| Appearance | Reddish-brown to violet powder or crystalline solid with no distinct odor. Non-volatile at room temperature and less reactive than white phosphorus. |
| Flash Point | Not applicable (ignites by friction/heat ~260C/500F) |
| Boiling Point | Not applicable (sublimes at 416C/781F under vacuum) |
| Vapor Density | Not applicable (solid) |
| Water Reactivity | No significant reaction with water; insoluble |
Fireground Response Guidance — UN 1338
Extinguishing Media
PPE Requirements
Use SCBA for fire, smoke, dust or confined-space exposure. Gloves, eye protection and protective clothing should be selected from SDS; avoid dust generation and contaminated residue contact.
Isolation & Evacuation
First Actions for a UN 1338 Incident
- CALL 911. Then call the emergency response telephone number on the shipping paper, if available.
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Eliminate ignition sources if it is safe to do so.
- Avoid creating dust clouds or spreading powder during movement or cleanup.
- Ventilate closed spaces before entering, but only if properly trained, equipped and authorized by incident command.
- Isolate the spill or fire area and expand the perimeter if large quantities, dust clouds or fire involvement are present.
- Use ERG Guide 133, shipping papers, SDS and incident command for protective actions and entry decisions.
📋 Copy & Share Field Card
UN 1338 — Phosphorus, amorphousUse 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.