UN 1699 — Diphenylchloroarsine, liquid
Placard: Toxic. ERG Guide 151. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1699 is Diphenylchloroarsine, liquid, a toxic arsenical irritant agent assigned to ERG Guide 151. Aerosol, smoke or dust exposure can cause severe eye and respiratory irritation plus arsenic contamination.
Hazard overview: UN 1699 presents toxic arsenic, lachrymator/aerosol and contaminated-runoff hazards. Fire or hydrolysis may create arsenic-containing residues and corrosive decomposition products.
Response guidance: For a UN 1699 incident, responders should verify the product with shipping papers, package markings, SDS and ERG Guide 151. Establish incident command, isolate the area, stay upwind, prevent dust, vapor or aerosol exposure, control runoff and choose entry or cleanup actions based on monitoring, SDS and local SOP.
Firefighter training notes: Training for UN 1699 should emphasize arsenic dust/aerosol exposure, contamination control, SCBA use, runoff containment and decontamination. Use ERG 151, SDS and local SOP.
Regulatory context: Diphenylchloroarsine, liquid is regulated as a toxic arsenic hazardous material. Transportation, workplace exposure, spill reporting, waste handling, storage and environmental requirements may vary by compound, concentration, quantity and jurisdiction. Verify current requirements through shipping papers, SDS, facility documents and applicable DOT, OSHA, EPA, NFPA, state or local authority guidance.
Storage & handling: Diphenylchloroarsine, liquid should be stored in tightly closed compatible containers in a secure, cool, dry, well-ventilated toxic-material area away from food, incompatible chemicals, heat and unauthorized access. Prevent dust release, leaks and contaminated runoff.
UN 1699 Quick Details
Common Hazards of UN 1699
- TOXIC arsenical irritant/lachrymator agent; inhalation, ingestion or skin contact may cause severe injury.
- Aerosol, dust or smoke can cause intense eye, respiratory and nausea-type irritation.
- Hydrolysis or fire may produce toxic arsenic-containing residues and corrosive decomposition products.
- Vapors, aerosols or smoke may accumulate in low or poorly ventilated areas.
- Fire may produce irritating, corrosive and/or toxic gases.
- Runoff may spread arsenic contamination.
- Avoid dust, smoke, aerosol and all unnecessary skin contact.
Chemical Identity & Physical Properties
Colorless to dark brown oily liquid with a geranium-like or irritating odor. Vesicant and lachrymator agent.
| Also known as | Clark IDADiphenylarsine chlorideDiphenylchloroarsineBlue CrossPhenylarsine dichloride |
| CAS Number | 712-48-1 |
| Appearance | Colorless to dark brown oily liquid with a geranium-like or irritating odor. Vesicant and lachrymator agent. |
| Flash Point | Not applicable (non-flammable liquid) |
| Boiling Point | 333C (631F) with decomposition |
| Vapor Density | 9.4 (much heavier than air) |
| Water Reactivity | Hydrolyzes slowly in water, producing toxic and corrosive fumes |
Fireground Response Guidance — UN 1699
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA and chemical protective clothing for aerosol, dust, smoke or unknown exposure. Level A may be needed for close entry; decontamination should address arsenic-containing residues.
Isolation & Evacuation
First Actions for a UN 1699 Incident
- CALL 911. Then call the emergency response telephone number on the shipping paper, if available.
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Avoid breathing vapors, fumes, dust, mist, aerosol or smoke and avoid all skin or eye contact.
- Do not touch or walk through spilled material unless properly trained and wearing appropriate protective equipment.
- Avoid creating dust clouds or spreading contaminated liquid, powder, solution, runoff or debris.
- Ventilate closed spaces before entering, but only if properly trained, equipped, monitored and authorized by incident command.
- Isolate the spill or leak area and expand the perimeter if vapor, dust, aerosol, fire involvement or unknown concentration is present.
- Use ERG Guide 151, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 1699 — Diphenylchloroarsine, liquidUse 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.