UN 3279 — Organophosphorus compound, poisonous, flammable, n.o.s.
Placard: Toxic. ERG Guide 131. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3279 At a Glance
UN 3279 (Organophosphorus compound, poisonous, flammable) is listed as DOT Class 6 Toxic and is assigned to ERG Guide 131. Use this page to review placard data, common hazards, PPE notes, isolation context, first actions, and related UN numbers.
UN 3279 is Organophosphorus compound, poisonous, flammable, n.o.s., a broad toxic flammable organophosphorus entry assigned to ERG Guide 131. Solvent flashback and dermal toxicity are key.
Hazard overview: TOXIC and FLAMMABLE organophosphorus compound, n.o.s.; inhalation, ingestion or skin absorption may be fatal. Vapors may ignite and form explosive mixtures with air. Skin contact and contaminated clothing can extend toxic exposure.
Response guidance: For UN 3279, isolate the area, eliminate ignition sources and keep vapors out of drains. Use SCBA, contain runoff and select foam/dry chemical/CO2 using SDS and ERG 131.
Firefighter training notes: Training for UN 3279 should emphasize high-toxicity exposure routes, skin absorption, SCBA/Level A decisions, decontamination, runoff control and exact-compound verification. Use ERG 131, SDS and local SOP.
Regulatory context: Organophosphorus compound, poisonous, flammable, n.o.s. is regulated as a hazardous material for transport and emergency response. Storage, reporting, exposure, waste and incident-notification duties depend on quantity, composition, concentration and jurisdiction; verify shipping papers, SDS and authority guidance.
Storage & handling: Organophosphorus compound, poisonous, flammable, n.o.s. should be stored in approved flammable-liquid containers with ventilation, ignition control, secondary containment and segregation from oxidizers and incompatible materials.
UN 3279 Quick Details
Common Hazards of UN 3279
- TOXIC and FLAMMABLE organophosphorus compound, n.o.s.; inhalation, ingestion or skin absorption may be fatal.
- Vapors may ignite and form explosive mixtures with air.
- Skin contact and contaminated clothing can extend toxic exposure.
- Some compounds may inhibit cholinesterase; exact product identity is critical.
- Fire may produce phosphorus oxides and irritating/toxic gases.
- Runoff may be toxic, flammable-contaminated and environmentally harmful.
- Exact organophosphorus compound, solvent and concentration must be verified from SDS.
Chemical Identity & Physical Properties
Variable appearance depending on specific compound; typically colorless to pale yellow liquid with mild to pungent odor. This is a generic category covering various organophosphorus compounds.
| Also known as | Organophosphorus poisonOrganophosphate compoundPhosphorus-containing toxic substanceOP compound n.o.s. |
| Appearance | Variable appearance depending on specific compound; typically colorless to pale yellow liquid with mild to pungent odor. This is a generic category covering various organophosphorus compounds. |
| Flash Point | Variable, typically 23°C to 61°C (73°F to 142°F) depending on specific compound |
| Boiling Point | Variable, typically 100°C to 300°C (212°F to 572°F) depending on specific compound |
| Vapor Density | Typically >1 (heavier than air) for most organophosphorus liquids |
| Water Reactivity | Some compounds may hydrolyze slowly in water; generally no violent reaction but may release toxic vapors |
Fireground Response Guidance — UN 3279
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA and full chemical protective clothing. Level A may be needed for unknown concentration, heavy vapor, splash or high skin-absorption risk.
Isolation & Evacuation
First Actions for a UN 3279 Incident
- Call 911 and the emergency response number on the shipping paper, if available.
- Keep unauthorized personnel away and establish incident command.
- Stay upwind, uphill and upstream.
- Eliminate ignition sources if this can be done safely.
- Avoid breathing vapor, dust, mist, smoke or fumes and avoid skin or eye contact.
- Do not touch damaged containers or spilled material without proper training and PPE.
- Prevent contaminated liquid, dust, runoff and decontamination waste from spreading.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 131, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 3279 — Organophosphorus compound, poisonous, flUse 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.