UN 3226 — Self-reactive solid type D
Placard: Flammable Solid. ERG Guide 149. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3226 is Self-reactive solid type D, a self-reactive type D solid assigned to ERG Guide 149. Heat, contamination and confinement can trigger decomposition.
Hazard overview: SELF-REACTIVE type D solid; heat, contamination, friction, shock or confinement can trigger self-accelerating decomposition. May ignite and burn violently; decomposition can continue without outside oxygen. Containers may rupture or explode if heated or if decomposition begins.
Response guidance: For UN 3226, isolate the area, keep heat/friction/shock/contamination away and use SCBA from a protected position. Cool exposures if safe and follow SDS/ERG 149.
Firefighter training notes: Training for UN 3226 should emphasize self-accelerating decomposition, temperature/control-temperature checks, contamination avoidance, remote cooling, evacuation triggers and runoff control. Use ERG 149, SDS and local SOP.
Regulatory context: Self-reactive solid type D is regulated as a hazardous material for transport and emergency response. Storage, reporting, exposure, waste and incident-notification duties depend on quantity, formulation, package type and jurisdiction; verify shipping papers, SDS and authority guidance.
Storage & handling: Self-reactive solid type D should be stored in approved compatible packages away from heat, sunlight, friction, shock, contamination, acids, bases, metals and reducing agents.
UN 3226 Quick Details
Common Hazards of UN 3226
- SELF-REACTIVE type D solid; heat, contamination, friction, shock or confinement can trigger self-accelerating decomposition.
- May ignite and burn violently; decomposition can continue without outside oxygen.
- Containers may rupture or explode if heated or if decomposition begins.
- Contamination with acids, bases, metals, reducing agents or incompatible organics may increase instability.
- Fire may produce large volumes of irritating, toxic and/or corrosive gases.
- Runoff may carry reactive residue and contaminated decomposition products.
- Exact formulation, dilution, package size and temperature limits must be verified from SDS and shipping papers.
Chemical Identity & Physical Properties
Solid material that varies in color and appearance depending on specific formulation. Generic classification covering various organic compounds capable of self-accelerating decomposition or polymerization at ambient or elevated temperatures.
| Also known as | Self-reactive solid type DOrganic peroxide type D solidSelf-accelerating decomposition materialSADM solid type D |
| Appearance | Solid material that varies in color and appearance depending on specific formulation. Generic classification covering various organic compounds capable of self-accelerating decomposition or polymerization at ambient or elevated temperatures. |
| Flash Point | Not applicable (self-reactive solid) |
| Boiling Point | Not applicable (decomposes before boiling) |
| Vapor Density | Not applicable (solid) |
| Water Reactivity | Generally no significant reaction with water, but decomposition may be accelerated by moisture in some formulations |
Fireground Response Guidance — UN 3226
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA, full protective clothing and distance/blast protection. Avoid contaminated PPE, friction, heat and direct contact with reactive residue.
Isolation & Evacuation
First Actions for a UN 3226 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.
- Keep heat, sparks, friction, shock and contamination away from the material.
- Avoid breathing vapor, dust, mist, smoke or fumes and avoid skin or eye contact.
- Do not touch damaged containers, spilled material or residue without proper training and PPE.
- Prevent contaminated runoff, dust, liquid 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 3226 — Self-reactive solid type DUse 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.