UN 2956 — 5-tert-Butyl-2,4,6-trinitrom- xylene
Placard: Flammable Solid. ERG Guide 149. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2956 At a Glance
UN 2956 (5-tert-Butyl-2,4,6-trinitrom- xylene) is listed as DOT Class 4 Flammable Solid and is assigned to ERG Guide 149. Use this page to review placard data, common hazards, PPE notes, isolation context, first actions, and related UN numbers.
UN 2956 is 5-tert-Butyl-2,4,6-trinitrom- xylene, a flammable energetic nitroaromatic solid assigned to ERG Guide 149. Heat, friction and decomposition risks require control.
Hazard overview: FLAMMABLE nitroaromatic solid; heat, friction, sparks or contamination may ignite it. May decompose violently if heated, confined or involved in fire. Dust may form explosive mixtures in air and increase sensitivity.
Response guidance: For UN 2956, isolate the area, avoid dust/friction and use SCBA. Use only compatible dry media, watch for re-ignition or violent decomposition and follow SDS/ERG 149.
Firefighter training notes: Training for UN 2956 should emphasize dry-media tactics, moisture/friction control, re-ignition, remote operations, SCBA use and runoff/debris control. Use ERG 149, SDS and local SOP.
Regulatory context: 5-tert-Butyl-2,4,6-trinitrom- xylene is regulated as a hazardous material for transport and emergency response. Storage, reporting, exposure, waste and incident-notification duties depend on quantity, formulation and jurisdiction; verify shipping papers, SDS and authority guidance.
Storage & handling: 5-tert-Butyl-2,4,6-trinitrom- xylene should be stored in tightly closed compatible containers with ventilation, secondary containment, restricted access and SDS-based segregation from incompatible materials.
UN 2956 Quick Details
Common Hazards of UN 2956
- FLAMMABLE nitroaromatic solid; heat, friction, sparks or contamination may ignite it.
- May decompose violently if heated, confined or involved in fire.
- Dust may form explosive mixtures in air and increase sensitivity.
- Burning may be intense and may produce large volumes of toxic gases.
- Fire may produce nitrogen oxides and irritating/toxic aromatic smoke.
- Runoff or residues may carry toxic energetic material contamination.
- Avoid impact, friction, dust generation and unnecessary handling.
Chemical Identity & Physical Properties
Yellow to white crystalline solid with a musk-like odor. Exists as crystals or powder at room temperature.
| Also known as | Musk xylene5-tert-Butyl-2,4,6-trinitro-m-xyleneMusk xylol1-tert-Butyl-3,5-dimethyl-2,4,6-trinitrobenzene |
| CAS Number | 81-15-2 |
| Appearance | Yellow to white crystalline solid with a musk-like odor. Exists as crystals or powder at room temperature. |
| Flash Point | Not applicable (explosive solid) |
| Boiling Point | Decomposes at approximately 205C (401F) |
| Vapor Density | Not applicable (solid) |
| Water Reactivity | Insoluble in water; no significant reaction with water |
Fireground Response Guidance — UN 2956
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for fire, dust or smoke. Wear flame/chemical protection and avoid dust, friction and incompatible media.
Isolation & Evacuation
First Actions for a UN 2956 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.
- Eliminate ignition sources if this can be done safely.
- Avoid breathing vapor, dust, gas, mist, smoke or fumes and avoid skin or eye contact.
- Do not touch damaged containers or spilled material without proper training and PPE.
- Prevent contaminated liquid, dust, runoff and decontamination waste from spreading.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 149, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 2956 — 5-tert-Butyl-2,4,6-trinitrom- xyleneUse 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.