UN 3555 — Trifluoromethyltetrazole-sodium salt in acetone
Placard: Flammable. ERG Guide 113. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3555 is Trifluoromethyltetrazole-sodium salt in acetone, assigned to ERG Guide 113. This entry should be verified with shipping papers, labels and the SDS before responders commit to close-range action.
Hazard overview: The acetone carrier is highly flammable and dried residue may become shock-sensitive. Heat, sparks, friction, flame or evaporation of solvent can greatly increase explosion risk.
Response guidance: Use ERG Guide 113, isolate the area, keep people upwind and avoid incompatible agents. Keep water away unless incident command confirms it is safe for the specific material.
UN 3555 Quick Details
Common Hazards of UN 3555
- Flammable/combustible material.
- May be ignited by heat, sparks or flames.
- DRIED OUT material may explode if exposed to heat, flame, friction or shock; treat as an
- Keep material wet with water or treat as an explosive (GUIDE 112).
- Runoff to sewer may create fire or explosion hazard.
- Some are toxic and may be fatal if inhaled, ingested or absorbed through skin. Specifically,
- Contact may cause burns to skin and eyes.
- Fire may produce irritating, corrosive and/or toxic gases.
Chemical Identity & Physical Properties
Clear to pale yellow liquid solution with characteristic acetone odor. Flammable liquid containing an organic salt that becomes shock-sensitive when dried.
| Also known as | Sodium trifluoromethyltetrazolate in acetoneNaTFMT in acetoneTrifluoromethyltetrazole sodium derivative solution |
| Appearance | Clear to pale yellow liquid solution with characteristic acetone odor. Flammable liquid containing an organic salt that becomes shock-sensitive when dried. |
| Flash Point | -20C (-4F) (acetone carrier) |
| Boiling Point | 56C (133F) (acetone component) |
| Vapor Density | 2.0 (heavier than air) |
| Water Reactivity | Dilutes in water; acetone is water-miscible but dried residue becomes extremely shock-sensitive |
Fireground Response Guidance — UN 3555
Extinguishing Media
PPE Requirements
Level B minimum with full face SCBA; avoid shock/friction with dried residue; treat any dried material as explosive. Select final PPE using ERG guidance, SDS, monitoring and incident command.
Isolation & Evacuation
First Actions for a UN 3555 Incident
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Ventilate closed spaces before entering, but only if properly trained and equipped.
- Isolate spill or leak area immediately for at least 100 meters (330 feet) in all directions.
- Consider initial evacuation for 500 meters (1/3 mile) in all directions.
📋 Copy & Share Field Card
UN 3555 — Trifluoromethyltetrazole-sodium salt inUse 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.