UN 0173 — Release devices, explosive
Placard: Explosive 1.4S. ERG Guide 114. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 0173 is Release devices, explosive, a Class 1.4 explosive article assigned to ERG Guide 114. It presents a limited fire or minor blast hazard, but responders still need isolation, smoke protection and shipment verification.
Hazard overview: UN 0173 generally has effects limited to the package or immediate area, but heat or fire can cause localized deflagration, popping, fragments and irritating smoke. The hazard may increase if other explosives, ammunition or pyrotechnics are nearby.
Response guidance: For a UN 0173 incident, responders should confirm the article using shipping papers, markings and ERG Guide 114. Isolate the area, keep personnel out of smoke, control ignition sources when safe, and expand the perimeter if fire involves larger quantities or adjacent explosives.
Firefighter training notes: Training should emphasize the difference between 1.4 limited-effect explosives and higher-hazard Class 1 materials. Common errors include standing too close to heated packages, dismissing smoke hazards and failing to check for adjacent explosives or ammunition.
Regulatory context: Release devices, explosive is regulated as a Class 1 explosive article for transportation. Storage, quantity limits, fire code controls and reporting requirements may vary by jurisdiction. Responders should verify current requirements through shipping papers, product documents and applicable DOT, ATF, OSHA, NFPA or local authority guidance.
Storage & handling: Release devices, explosive should be stored in compatible packaging away from heat, sparks, open flame, impact and unauthorized access. Keep separated from incompatible explosives, propellants and combustible clutter according to product instructions and local fire code.
UN 0173 Quick Details
Common Hazards of UN 0173
- Minor explosive and fire hazard with effects usually limited to the package or immediate area.
- Localized burning, deflagration, popping or small fragments may occur if heated.
- Smoke and heat from burning articles may irritate the eyes and respiratory tract.
- Low mass explosion risk under normal transport conditions.
- Heated packages may fail and scatter small articles or fragments.
- Nearby explosives, ammunition or pyrotechnics may increase the overall incident hazard.
Chemical Identity & Physical Properties
Metal or composite assemblies containing small explosive charges designed to mechanically release or separate components. Typically solid devices in various configurations.
| Also known as | Explosive release devicesPyrotechnic release mechanismsExplosive actuatorsOrdnance release systems |
| Appearance | Metal or composite assemblies containing small explosive charges designed to mechanically release or separate components. Typically solid devices in various configurations. |
| Flash Point | Not applicable (explosive device) |
| Boiling Point | Not applicable (explosive device) |
| Vapor Density | Not applicable (solid device) |
| Water Reactivity | No significant reaction under normal conditions |
Fireground Response Guidance — UN 0173
Extinguishing Media
PPE Requirements
Structural firefighting protective clothing with SCBA is appropriate for fire or smoke exposure, with distance maintained from heated packages. Approach and handling should follow incident command and local SOP.
Isolation & Evacuation
First Actions for a UN 0173 Incident
- CALL 911. Notify law enforcement if ammunition components, explosive articles or ordnance are involved.
- Keep unauthorized personnel away.
- Stage upwind and avoid smoke from burning articles.
- Eliminate ignition sources if it is safe to do so.
- Isolate the area and expand the perimeter if fire grows or additional explosives are present.
- Use ERG Guide 114, shipping papers and incident command for isolation and fire response decisions.
📋 Copy & Share Field Card
UN 0173 — Release devices, explosiveUse 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.