UN 0312 — Cartridges, signal
Placard: Explosive 1.4G. ERG Guide 114. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 0312 refers to Cartridges, signal — small pyrotechnic devices designed to produce light, smoke, or sound for signaling purposes, classified as Class 1 Explosive (1.4G). Though considered low-risk explosives, they contain reactive compositions that can ignite, deflagrate, or produce hazardous smoke when damaged or exposed to heat.
Hazard overview: UN 0312 signal cartridges pose a localized fire and deflagration risk, with burning capable of generating intense heat and toxic smoke from pyrotechnic compositions. Damaged or compromised cartridges may contain water-reactive materials, making uncontrolled burning difficult to suppress safely.
Response guidance: Isolate the affected area for at least 25–50 meters in all directions immediately; if fire is involved, establish an 800-meter evacuation radius per ERG Guide 114. Do not apply water directly to damaged cartridges — use dry chemical, sand, or CO2 to control fire, and limit water fog to cooling nearby exposed materials only.
UN 0312 Quick Details
Common Hazards of UN 0312
- Minor blast or fire hazard — limited effect.
- Localized burning or deflagration possible.
- Smoke and heat from burning.
- Low mass explosion risk under normal conditions.
Chemical Identity & Physical Properties
UN 0312 cartridges are small cylindrical metal or plastic devices containing pyrotechnic compositions, with color-coded or labeled exteriors identifying their signal type (light, smoke, or sound).
| Also known as | Signal cartridgesPyrotechnic signal devicesFlare cartridgesDistress signal cartridges |
| Appearance | Small cylindrical devices containing pyrotechnic compositions for producing light, smoke, or sound signals. Typically metal or plastic casings with colored or marked exteriors indicating signal type. |
| Flash Point | Not applicable (pyrotechnic device) |
| Boiling Point | Not applicable (solid pyrotechnic composition) |
| Vapor Density | Not applicable (solid device) |
| Water Reactivity | May contain water-reactive pyrotechnic materials; avoid water contact with damaged cartridges |
Fireground Response Guidance — UN 0312
Extinguishing Media
PPE Requirements
Responders must wear standard firefighting PPE with SCBA and eye or face protection during all handling or fire suppression operations involving UN 0312.
Isolation & Evacuation
First Actions for a UN 0312 Incident
- CALL 911. Notify law enforcement.
- Isolate area; keep unauthorized personnel away.
- Stage upwind; eliminate ignition sources.
- Request Hazmat + law enforcement.
- Consult current ERG Guide 114 and follow SOP/SOG.
📋 Copy & Share Field Card
UN 0312 — 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.