UN 3139 — Oxidizing liquid, n.o.s.
Placard: Oxidizer. ERG Guide 140. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
Oxidizing liquid, n.o.s. covers liquid oxidizers whose exact chemistry must be verified. The main concern is fire intensification and reaction with incompatible materials.
Hazard overview: UN 3139 can make combustible materials burn faster or more violently. Some products can react with organic absorbents, fuels or reducing agents and may release corrosive or toxic vapors when heated.
Response guidance: Isolate the spill, keep combustibles away and prevent product from entering drains. Use noncombustible diking materials and select extinguishing agents based on the SDS and ERG 140.
Firefighter training notes: Train responders to avoid organic absorbents on oxidizer spills and to separate oxidizers from fuels during salvage and overhaul. Verify compatibility before diking.
Regulatory context: UN 3139 is a Class 5.1 n.o.s. oxidizing liquid entry. Product-specific shipping papers and SDS determine subsidiary hazards and reportable requirements.
Storage & handling: Store cool and separated from combustibles, organic material, reducing agents, acids and contamination sources. Use compatible containers and noncombustible spill control.
UN 3139 Quick Details
Common Hazards of UN 3139
- Oxidizing liquid that can intensify burning of nearby combustible materials.
- May react dangerously with fuels, oils, organic material, reducing agents or contaminated absorbents.
- Some products under this n.o.s. entry may decompose violently when heated.
- Contact can cause chemical burns or severe irritation depending on the specific oxidizer.
- Fire may produce toxic or corrosive vapors.
- Containers may rupture or explode if heated or contaminated.
- Exact water reactivity and suppression choices depend on the product SDS.
Chemical Identity & Physical Properties
Appearance, odor and vapor behavior vary widely. Treat the liquid as oxidizing and potentially corrosive until the exact chemical is confirmed.
| Also known as | Oxidizing liquid NOSOxidizing liquid not otherwise specifiedClass 5.1 oxidizing liquidLiquid oxidizer NOS |
| Appearance | Variable appearance depending on specific oxidizer; typically clear to colored liquids with little or no odor at room temperature. Physical properties vary widely as this is a generic shipping classification. |
| Flash Point | Not applicable (oxidizer) |
| Boiling Point | Variable depending on specific oxidizer |
| Vapor Density | Variable depending on specific oxidizer |
| Water Reactivity | Variable; some may react vigorously with water or organic materials. Avoid contact with combustibles. |
Fireground Response Guidance — UN 3139
Extinguishing Media
PPE Requirements
Use SCBA, splash protection and chemical-resistant clothing. Avoid leather, cotton or contaminated clothing that could retain oxidizer and later ignite.
Isolation & Evacuation
First Actions for a UN 3139 Incident
- Call 911 and the emergency response number shown on the shipping paper, if available.
- Keep unauthorized personnel away and establish incident command before close approach.
- Stay upwind, uphill and upstream; avoid low areas where vapors or gases may collect.
- Avoid breathing vapors, dust, mist or fire gases and avoid skin or eye contact.
- Do not touch damaged containers or spilled material without proper PPE and training.
- Ventilate confined spaces only if trained, equipped and authorized by incident command.
- Use ERG guidance, SDS, shipping papers and monitoring results for final protective actions.
📋 Copy & Share Field Card
UN 3139 — Oxidizing liquid, n.o.s.Use 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.