UN 3464 — Organophosphorus compound, solid, poisonous, n.o.s.
Placard: Toxic. ERG Guide 151. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3464 is Organophosphorus compound, solid, poisonous, n.o.s., a broad highly toxic organophosphorus solid assigned to ERG Guide 151. Exact compound and cholinesterase risk must be verified.
Hazard overview: HIGHLY TOXIC organophosphorus solid, n.o.s.; inhalation, ingestion or skin absorption may be fatal. Some organophosphorus compounds may inhibit cholinesterase; exact identity is critical for medical and decon planning. Dust can contaminate clothing, tools and cleanup equipment.
Response guidance: For UN 3464, isolate the area, avoid all skin contact and use SCBA with chemical protection. Prevent runoff spread and verify exact compound with SDS and ERG 151.
Firefighter training notes: Training for UN 3464 should emphasize high-toxicity exposure routes, skin absorption, SCBA/Level A decisions, decontamination, runoff control and exact-compound verification. Use ERG 151, SDS and local SOP.
Regulatory context: Organophosphorus compound, solid, poisonous, 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, concentration, formulation and jurisdiction; verify shipping papers, SDS and authority guidance.
Storage & handling: Organophosphorus compound, solid, poisonous, n.o.s. should be stored in tightly closed compatible containers with restricted access, ventilation, secondary containment and segregation from moisture, oxidizers and incompatible materials per SDS.
UN 3464 Quick Details
Common Hazards of UN 3464
- HIGHLY TOXIC organophosphorus solid, n.o.s.; inhalation, ingestion or skin absorption may be fatal.
- Some organophosphorus compounds may inhibit cholinesterase; exact identity is critical for medical and decon planning.
- Dust can contaminate clothing, tools and cleanup equipment.
- Combustibility and water behavior vary by exact compound.
- Fire may produce phosphorus oxides and toxic decomposition gases.
- Runoff may carry persistent toxic organophosphorus contamination.
- Exact active compound, purity and formulation must be verified from SDS.
Chemical Identity & Physical Properties
Variable appearance depending on specific compound; typically white to tan crystalline solid or powder with little to no odor at room temperature. Highly toxic organophosphorus materials.
| Also known as | Organophosphate compound solidPhosphorus organic compound solidOrganophosphorus solid NOSOP compound solid |
| Appearance | Variable appearance depending on specific compound; typically white to tan crystalline solid or powder with little to no odor at room temperature. Highly toxic organophosphorus materials. |
| Flash Point | Variable, depends on specific compound; many are non-flammable solids |
| Boiling Point | Variable, depends on specific compound; many decompose before boiling |
| Vapor Density | Not applicable (solid at room temperature) |
| Water Reactivity | Variable; some organophosphorus compounds may hydrolyze slowly in water, releasing toxic vapors |
Fireground Response Guidance — UN 3464
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA and full chemical protective clothing. Level A may be needed for unknown compound, dust, vapor, splash or high skin-absorption risk.
Isolation & Evacuation
First Actions for a UN 3464 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.
- Avoid breathing vapor, dust, mist, smoke or fumes and avoid skin or eye contact.
- Do not touch damaged containers, equipment 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 151, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 3464 — Organophosphorus compound, solid, poisonUse 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.