UN 2546 — Titanium powder, dry
Placard: Spontaneously Combustible. ERG Guide 135. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2546 At a Glance
UN 2546 (Titanium powder, dry) is listed as DOT Class 4 Spontaneously Combustible and is assigned to ERG Guide 135. Use this page to review placard data, common hazards, PPE notes, isolation context, first actions, and related UN numbers.
Dry titanium powder is a reactive metal powder shipped as UN 2546. Fine dry particles can ignite in air or moist conditions and can burn with intense heat.
Hazard overview: Titanium powder presents spontaneous combustion, dust ignition and re-ignition hazards. Water, foam or CO2 may be unsafe on burning powder unless the SDS and incident command confirm otherwise.
Response guidance: Isolate the area, avoid disturbing powder and keep ignition sources away. Use Class D dry powder, dry sand or other approved dry media. Monitor for re-ignition after control.
Firefighter training notes: Train firefighters on Class D metal fire tactics, dry media placement and avoiding dust disturbance. Include re-ignition watch procedures.
Regulatory context: UN 2546 is transported as Titanium powder, dry, Class 4 spontaneously combustible material. Confirm package condition and exact product form.
Storage & handling: Store dry in closed containers away from moisture, oxidizers, acids, heat and ignition sources. Prevent powder leaks and dust buildup.
UN 2546 Quick Details
Common Hazards of UN 2546
- Dry titanium powder is a spontaneously combustible metal powder; fine particles can ignite in air or moist air.
- Burning powder can produce an intense, very hot metal fire.
- Dust clouds may flash or explode if dispersed near an ignition source.
- Water, foam or CO2 may react, spread burning powder or worsen the incident.
- Moisture can promote heating and ignition in finely divided material.
- Fire may produce irritating titanium oxide smoke.
- Material may re-ignite after apparent extinguishment.
Chemical Identity & Physical Properties
Titanium powder is a gray to dark gray metallic powder. The finer and drier the powder, the greater the ignition and dust fire hazard.
| Also known as | Titanium metal powderTitanium dustTi powderTitanium particulate |
| CAS Number | 7440-32-6 |
| Appearance | Gray to dark gray metallic powder. Odorless. Exists as a fine to coarse dry powder at room temperature. |
| Flash Point | Not applicable (pyrophoric metal powder) |
| Boiling Point | 3287C (5949F) |
| Vapor Density | Not applicable (solid metal powder) |
| Water Reactivity | Reacts with moisture in air; may ignite spontaneously when damp or in humid conditions |
Fireground Response Guidance — UN 2546
Extinguishing Media
PPE Requirements
Use SCBA for smoke, dust or unknown atmosphere. Fire-resistant clothing and protective equipment suitable for reactive metal fires are required.
Isolation & Evacuation
First Actions for a UN 2546 Incident
- Call 911 and the emergency response number on the shipping papers.
- Keep unauthorized personnel away and avoid disturbing the powder.
- Stay upwind, uphill and upstream of dust and smoke.
- Avoid breathing dust or smoke; prevent skin and eye contact.
- Do not touch damaged containers without PPE and reactive-metal response guidance.
- Keep water and incompatible extinguishing agents away from burning powder.
- Use ERG 135, SDS and shipping papers to confirm dry media, isolation and cleanup tactics.
📋 Copy & Share Field Card
UN 2546 — Titanium powder, dryUse 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.