UN 0405 — Cartridges, signal
Placard: Explosive 1.4S. ERG Guide 114. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 0405 is Cartridges, signal, 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 0405 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 0405 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, disturbing damaged articles and failing to check for adjacent explosives or ammunition.
Regulatory context: Cartridges, signal is regulated as a Class 1 explosive hazardous material. Transportation, storage, quantity limits, fire code controls and reporting requirements may vary by jurisdiction. Responders should verify current requirements through shipping papers, SDS or product documents and applicable DOT, ATF, OSHA, NFPA, military, state or local authority guidance.
Storage & handling: Cartridges, signal should be stored only in approved packaging, magazines or authorized explosive storage areas, separated from ignition sources, incompatible materials and unauthorized access. Packages should be protected from heat, impact, friction, moisture where relevant and physical damage according to product documentation and applicable explosive storage regulations.
UN 0405 Quick Details
Common Hazards of UN 0405
- Minor explosive and fire hazard with effects usually limited to the device or package.
- Smoke or burning output may reduce visibility and irritate the eyes or respiratory tract.
- Localized burning, deflagration, popping or small fragments may occur if heated.
- 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
Small cylindrical devices containing pyrotechnic compositions, typically metal or plastic cased. Designed to produce colored smoke, flame, or light signals. Solid at room temperature.
| Also known as | Signal cartridgesPyrotechnic signal devicesFlare cartridgesDistress signal cartridges |
| Appearance | Small cylindrical devices containing pyrotechnic compositions, typically metal or plastic cased. Designed to produce colored smoke, flame, or light signals. Solid at room temperature. |
| Flash Point | Not applicable (pyrotechnic device) |
| Boiling Point | Not applicable (pyrotechnic solid) |
| Vapor Density | Not applicable (solid device) |
| Water Reactivity | May contain water-reactive pyrotechnic compounds; avoid water contact during fire |
Fireground Response Guidance — UN 0405
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 0405 Incident
- CALL 911. Notify law enforcement if explosive articles, ordnance or blasting components are involved.
- Keep unauthorized personnel away.
- Stage upwind and avoid smoke from burning articles.
- Move unprotected people out of the smoke path when safe and practical.
- 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 0405 — Cartridges, signalUse 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.