UN 1773 — Ferric chloride, anhydrous
Placard: Corrosive. ERG Guide 157. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1773 is Ferric chloride, anhydrous, a corrosive hazardous material assigned to ERG Guide 157. Responders should verify the exact product with shipping papers, container markings and SDS before close action.
Hazard overview: UN 1773 presents corrosive exposure hazards and may create toxic/corrosive gases or runoff in fire or incompatible contact. Use ERG, SDS and incident command to set isolation, PPE and control actions.
Response guidance: For a UN 1773 incident, responders should verify the product with shipping papers, package markings, SDS and ERG Guide 157. Establish incident command, isolate the area, stay upwind, prevent incompatible contact, control runoff and choose entry or fire-control actions based on monitoring, SDS and local SOP.
Firefighter training notes: Training for UN 1773 should emphasize corrosive exposure routes, water or oxidizer incompatibility where applicable, air monitoring, PPE selection, decontamination and runoff containment. Use ERG 157, SDS and local SOP.
Regulatory context: Ferric chloride, anhydrous is regulated as a hazardous material for transportation and emergency response purposes. Transportation, workplace exposure, spill reporting, pesticide/waste handling where applicable, storage and environmental requirements may vary by formulation, 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: Ferric chloride, anhydrous should be stored in tightly closed compatible containers in a secure, cool, dry, well-ventilated hazardous-material area according to SDS and local procedures.
UN 1773 Quick Details
Common Hazards of UN 1773
- CORROSIVE material; inhalation, ingestion or skin/eye contact may cause severe injury.
- Fire may produce irritating, corrosive and/or toxic gases.
- Runoff may be corrosive and may pollute waterways.
- Containers may rupture or fail when heated.
- Specific hazards depend on the exact product, concentration and SDS.
Chemical Identity & Physical Properties
Dark brown to black crystalline solid or reddish-brown lumps with a faint hydrochloric acid odor. Highly hygroscopic and deliquescent in moist air.
| Also known as | Iron(III) chlorideIron trichlorideFerric trichlorideFlores martis |
| CAS Number | 7705-08-0 |
| Appearance | Dark brown to black crystalline solid or reddish-brown lumps with a faint hydrochloric acid odor. Highly hygroscopic and deliquescent in moist air. |
| Flash Point | Not applicable (non-flammable inorganic solid) |
| Boiling Point | 316C (601F) with decomposition |
| Vapor Density | Not applicable (solid; however releases dense HCl vapors when exposed to moisture) |
| Water Reactivity | Reacts exothermically with water producing heat and corrosive hydrochloric acid fumes; violent reaction with moisture |
Fireground Response Guidance — UN 1773
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for vapor, mist, dust, fire or confined-space exposure. Chemical-resistant gloves, boots, eye/face protection and protective clothing should be selected from SDS.
Isolation & Evacuation
First Actions for a UN 1773 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 or spray and avoid skin or eye contact.
- Do not touch or walk through spilled material unless properly trained and wearing appropriate protective equipment.
- 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, fire involvement, water reaction or unknown concentration is present.
- Use ERG Guide 157, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 1773 — Ferric chloride, anhydrousUse 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.