UN 0072 — Cyclonite; RDX; Hexogen, wetted
Placard: Explosive 1.1D. ERG Guide 112. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 0072, known as RDX or Hexogen wetted, is a powerful military and commercial explosive shipped in a water- or alcohol-wetted state to reduce its sensitivity to accidental detonation. The wetting agent acts as a desensitizer, but if the material dries out, it becomes extremely sensitive to heat, shock, and friction.
Hazard overview: UN 0072 presents a mass explosion hazard, meaning the entire load can detonate simultaneously, producing catastrophic blast overpressure and high-velocity fragmentation. Even in its wetted state, RDX remains sensitive to ignition sources, and any fire involvement must be treated as an imminent detonation risk.
Response guidance: Per ERG Guide 112, responders must isolate a minimum of 500 meters (1,600 ft) in all directions and evacuate at least 1,600 meters (1 mile) downwind if the material is involved in fire. Immediate withdrawal is required upon any sign of fire exposure, as no intervention can be safely conducted once detonation risk is elevated.
UN 0072 Quick Details
Common Hazards of UN 0072
- Mass explosion hazard — entire load may detonate simultaneously.
- Severe blast overpressure and fragmentation.
- Sensitive to heat, shock, and friction.
- Secondary fire and debris hazard.
Chemical Identity & Physical Properties
UN 0072 is a white, odorless crystalline solid that is shipped wetted with water or alcohol to stabilize it during transport, but becomes an extremely hazardous dry explosive if the desensitizing agent evaporates.
| Also known as | RDXHexogenCyclotrimethylenetrinitramineT41,3,5-Trinitro-1,3,5-triazacyclohexaneHexahydro-1,3,5-trinitro-1,3,5-triazine |
| CAS Number | 121-82-4 |
| Appearance | White crystalline solid, odorless. Shipped wetted with water or alcohol to reduce sensitivity. Stable when properly desensitized but extremely hazardous when dry. |
| Flash Point | Not applicable (explosive solid) |
| Boiling Point | Not applicable (decomposes explosively at approximately 230C/446F) |
| Vapor Density | Not applicable (solid) |
| Water Reactivity | No reaction with water; wetting agent used as desensitizer |
Fireground Response Guidance — UN 0072
Extinguishing Media
PPE Requirements
Maximum protective distance and structural cover are required near UN 0072, as standard structural firefighters' protective clothing provides no meaningful protection against explosive blast or fragmentation.
Isolation & Evacuation
First Actions for a UN 0072 Incident
- CALL 911. Then call emergency response telephone number on shipping paper.
- Establish large isolation zone — minimum 500 meters in all directions.
- Stage upwind, uphill; limit personnel to essential responders only.
- Request Hazmat + law enforcement + additional resources immediately.
- Do not fight fire — evacuate and isolate; let burn if no life safety risk.
- Protect exposures only if safe and directed by command.
- Consult current ERG Guide 112 and follow SOP/SOG.
📋 Copy & Share Field Card
UN 0072 — Cyclonite; RDX; Hexogen, wettedUse 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.