UN 1326 — Hafnium powder, wetted with not less than 25% water
Placard: Flammable Solid. ERG Guide 170. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
Hafnium powder, wetted with not less than 25% water, is a highly reactive substance that requires careful handling. This substance is classified as a flammable solid and must be handled with caution.
Hazard overview: May react violently or explosively on contact with water; Some are transported in flammable liquids.
Response guidance: Isolate spill 25m in all directions. If fire, isolate 800m and consider evacuation 800m downwind. Use dry sand, dry chemical, or soda ash to extinguish.
UN 1326 Quick Details
Common Hazards of UN 1326
- May react violently or explosively on contact with water.
- Some are transported in flammable liquids.
- May be ignited by friction, heat, sparks or flames.
- Some of these materials will burn with intense heat.
- Dusts or fumes may form explosive mixtures in air.
- Containers may explode when heated.
- May re-ignite after fire is extinguished.
- Oxides from metallic fires are a severe health hazard.
Chemical Identity & Physical Properties
Gray to silver metallic powder, odorless. Shipped wetted with minimum 25% water to reduce pyrophoric hazard.
| Also known as | Hafnium metal powderHafnium powder wettedHf powderHafnium flammable solid |
| CAS Number | 7440-58-6 |
| Appearance | Gray to silver metallic powder, odorless. Shipped wetted with minimum 25% water to reduce pyrophoric hazard. |
| Flash Point | Not applicable (pyrophoric metal powder when dry) |
| Boiling Point | 4603C (8317F) |
| Vapor Density | Not applicable (solid metal) |
| Water Reactivity | Reacts with water when dry, generating heat and hydrogen gas. Wetted form designed to prevent ignition. |
Fireground Response Guidance — UN 1326
Extinguishing Media
PPE Requirements
Level B minimum; full face respirator, chemical-resistant gloves and suit. SCBA if fire involved.
Isolation & Evacuation
First Actions for a UN 1326 Incident
- Stay upwind, uphill and/or upstream.
- Keep unauthorized personnel away.
- Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters
- Consider initial downwind evacuation for at least 50 meters (160 feet).
📋 Copy & Share Field Card
UN 1326 — Hafnium powder, wetted with not less thaUse 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.