UN 3496 — Batteries, nickel-metal hydride
Placard: Miscellaneous. ERG Guide 171. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3496 is Batteries, nickel-metal hydride, a Class 9 article assigned to ERG Guide 171. Main concerns are heat exposure, rupture, short circuit, electrolyte release and smoke from damaged units.
Hazard overview: Primary hazards include toxic exposure, fire or vapor ignition. Batteries, nickel-metal hydride may release irritating, toxic or corrosive vapors when heated, spilled or involved in fire, so avoid contact, inhalation and incompatible materials.
Response guidance: For a UN 3496 incident, establish incident command, isolate the area, stay upwind and uphill, keep unauthorized personnel away, verify shipping papers/SDS and follow ERG 171. Use extinguishing, cooling, containment and decontamination tactics only when compatible with the material and local SOP.
UN 3496 Quick Details
Common Hazards of UN 3496
- Some may burn but none ignite readily.
- Containers may explode when heated.
- Some may be transported hot.
- For UN3508, Capacitor, asymmetric, be aware of possible short circuiting as this product is transported
- Polymeric beads, expandable (UN2211) may evolve flammable vapours.
- Inhalation of material may be harmful.
- Contact may cause burns to skin and eyes.
- Inhalation of Asbestos dust may have a damaging effect on the lungs.
Chemical Identity & Physical Properties
Sealed cylindrical or prismatic metal containers housing nickel hydroxide and metal hydride electrodes in alkaline electrolyte. Typically silver or blue-gray casing at ambient temperature.
| Also known as | NiMH batteriesNickel-metal hydride cellsRechargeable nickel-metal hydride batteriesNiMH power cells |
| Appearance | Sealed cylindrical or prismatic metal containers housing nickel hydroxide and metal hydride electrodes in alkaline electrolyte. Typically silver or blue-gray casing at ambient temperature. |
| Flash Point | Not applicable (sealed battery) |
| Boiling Point | Not applicable (sealed battery) |
| Vapor Density | Not applicable (sealed battery) |
| Water Reactivity | No significant reaction under normal conditions; damaged batteries may release alkaline electrolyte (potassium hydroxide) which reacts with water |
Fireground Response Guidance — UN 3496
Extinguishing Media
PPE Requirements
Level D for intact batteries; chemical-resistant gloves and eye protection for damaged/leaking units; alkaline electrolyte is corrosive
Isolation & Evacuation
First Actions for a UN 3496 Incident
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters
- For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances.
- For non-highlighted materials: increase the immediate precautionary measure distance, in the downwind
📋 Copy & Share Field Card
UN 3496 — Batteries, nickel-metal hydrideUse 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.