UN 3219 — Nitrites, inorganic, aqueous solution, n.o.s.
Placard: Oxidizer. ERG Guide 140. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3219 Nitrites, inorganic, aqueous solution, n.o.s. is an oxidizing material. Response depends on the exact salt, concentration and contaminants present.
Hazard overview: Oxidizers supply oxygen or promote combustion. They can intensify fires, react with fuels or reducing agents, and release irritating decomposition gases when heated. Nitrite solutions may release toxic nitrogen oxides if acidified.
Response guidance: Isolate the spill, remove combustibles and prevent contamination. Cool exposed containers from a safe distance when compatible, and choose extinguishing media using ERG 140 and product-specific SDS.
Firefighter training notes: Train crews to separate oxidizers from fuels, organics and reducing agents, and to cool exposed containers from a safe distance when compatible.
Regulatory context: Class 5.1 oxidizers must be segregated from combustible materials, organic liquids, reducing agents and incompatible acids as required by shipping papers and local code.
Storage & handling: Store away from combustibles, oils, organic materials, reducing agents and heat. Prevent contamination of containers, residue and spill cleanup tools.
UN 3219 Quick Details
Common Hazards of UN 3219
- Oxidizer can intensify fire even though it may not be combustible itself.
- Heat, contamination or contact with fuels, organics or reducing agents can cause rapid decomposition.
- Containers may rupture or explode when heated.
- Spills can make combustible materials easier to ignite.
- Fire may release irritating, toxic or corrosive decomposition gases.
- Runoff may remain oxidizing and can contaminate drains or waterways.
- Exact oxidizer concentration and additives must be verified from SDS and shipping papers.
Chemical Identity & Physical Properties
Clear to slightly colored aqueous solution with little to no odor. Liquid at room temperature. Specific appearance depends on the nitrite salt dissolved.
| Also known as | Inorganic nitrite solutionNitrite salts in waterAqueous nitrite solutionNitrous acid salts solution |
| Appearance | Clear to slightly colored aqueous solution with little to no odor. Liquid at room temperature. Specific appearance depends on the nitrite salt dissolved. |
| Flash Point | Not applicable (non-flammable aqueous solution) |
| Boiling Point | Approximately 100C (212F), varies with concentration |
| Vapor Density | Not applicable (aqueous solution, vapor is primarily water) |
| Water Reactivity | Already in aqueous solution; may react with acids to release toxic nitrogen oxides |
Fireground Response Guidance — UN 3219
Extinguishing Media
PPE Requirements
Use SCBA and chemical-resistant clothing for spills, fire or unknown concentration. Keep PPE and tools free of oils, fuels and organic contamination.
Isolation & Evacuation
First Actions for a UN 3219 Incident
- Call 911 and the emergency response number 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, smoke or decomposition products and avoid skin or eye contact.
- Do not touch damaged containers or spilled material without appropriate PPE and monitoring.
- Ventilate confined spaces only if trained, equipped and authorized by incident command.
- Use ERG, SDS, shipping papers and atmospheric/radiation monitoring for final isolation and control decisions.
📋 Copy & Share Field Card
UN 3219 — Nitrites, inorganic, aqueous solution, nUse 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.