UN 3091 — Lithium metal batteries contained in equipment (including lithium alloy batteries)
Placard: Miscellaneous. ERG Guide 138. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3091 is Lithium metal batteries contained in equipment (including lithium alloy batteries), a lithium metal battery-in-equipment entry assigned to ERG Guide 138. Hidden damaged cells complicate response.
Hazard overview: Lithium metal batteries can enter thermal runaway if damaged, short-circuited, overheated or improperly charged. Fire may produce flammable gases, toxic smoke and corrosive fluoride-containing vapors. Cells may vent, rupture or eject burning material.
Response guidance: For UN 3091, isolate damaged or burning batteries, use SCBA for smoke and cool exposures. Prevent short circuits, monitor for re-ignition and follow ERG 138/local SOP.
Firefighter training notes: Training for UN 3091 should emphasize thermal runaway, re-ignition monitoring, smoke toxicity, water cooling decisions, damaged-battery handling and runoff control. Use ERG 138 and local SOP.
Regulatory context: Lithium metal batteries contained in equipment (including lithium alloy batteries) is regulated as a hazardous material for transport and emergency response. Storage, reporting, exposure, waste and incident-notification duties depend on quantity, formulation and jurisdiction; verify shipping papers, SDS and authority guidance.
Storage & handling: Lithium metal batteries contained in equipment (including lithium alloy batteries) should be stored to prevent short circuits, crushing, heat exposure and moisture damage, with segregation from combustibles and damaged-battery containment per carrier/local requirements.
UN 3091 Quick Details
Common Hazards of UN 3091
- Lithium metal batteries can enter thermal runaway if damaged, short-circuited, overheated or improperly charged.
- Fire may produce flammable gases, toxic smoke and corrosive fluoride-containing vapors.
- Cells may vent, rupture or eject burning material.
- Damaged batteries can re-ignite after apparent extinguishment.
- Water may be used for cooling and exposure protection, but runoff can be contaminated.
- Batteries contained in equipment may hide damaged cells and complicate access.
- Avoid short circuits, crushing and unprotected handling of damaged batteries.
Chemical Identity & Physical Properties
Sealed battery cells or battery packs integrated within electronic equipment. Typically metallic casing, gray or silver in color. Solid state at room temperature.
| Also known as | Lithium metal batteriesLithium alloy batteriesEquipment with lithium batteriesLithium battery powered devices |
| Appearance | Sealed battery cells or battery packs integrated within electronic equipment. Typically metallic casing, gray or silver in color. Solid state at room temperature. |
| Flash Point | Not applicable (sealed battery system) |
| Boiling Point | Not applicable (sealed battery system) |
| Vapor Density | Not applicable (solid battery) |
| Water Reactivity | Lithium metal reacts vigorously with water producing flammable hydrogen gas and heat if battery casing is compromised. Intact batteries pose minimal water reactivity risk. |
Fireground Response Guidance — UN 3091
Extinguishing Media
PPE Requirements
Use SCBA for smoke/fire and full protective clothing. Chemical-resistant gloves and eye protection are needed for leaking electrolyte or damaged cells.
Isolation & Evacuation
First Actions for a UN 3091 Incident
- Call 911 and establish incident command.
- Keep unauthorized personnel away from damaged, smoking or burning batteries.
- Stay upwind of smoke and vapors.
- Avoid touching damaged cells, leaking electrolyte or hot equipment without proper PPE.
- Prevent short circuits and keep damaged batteries separated from combustibles.
- Monitor for re-ignition after apparent extinguishment.
- Use ERG Guide 138, shipping papers, battery markings and local lithium-battery SOP for isolation and cleanup.
📋 Copy & Share Field Card
UN 3091 — Lithium metal batteries contained in equUse 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.