UN 1775 — Fluoroboric acid
Placard: Corrosive. ERG Guide 154. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1775 is Fluoroboric acid, a toxic corrosive fluoride-containing acid assigned to ERG Guide 154. Mist or solution can burn tissue and runoff may carry acidic fluoride contamination.
Hazard overview: UN 1775 presents corrosive acid, fluoride exposure, metal-reactivity and contaminated-runoff hazards. Fire or decomposition may release toxic/corrosive fumes.
Response guidance: For a UN 1775 incident, responders should verify the product with shipping papers, package markings, SDS and ERG Guide 154. 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 1775 should emphasize corrosive exposure routes, water or oxidizer incompatibility where applicable, air monitoring, PPE selection, decontamination and runoff containment. Use ERG 154, SDS and local SOP.
Regulatory context: Fluoroboric acid 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: Fluoroboric acid 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 1775 Quick Details
Common Hazards of UN 1775
- TOXIC and CORROSIVE fluoride-containing acid; inhalation, ingestion or contact may cause severe injury.
- Mist or solution can burn eyes, skin and respiratory tissue.
- Heating, decomposition or incompatible contact may release toxic/corrosive fluoride and boron-containing fumes.
- Corrosive liquid may react with metals to release flammable hydrogen gas.
- Runoff may carry acidic fluoride contamination.
- Containers may rupture or fail when heated.
- Avoid skin contact and control drains.
Chemical Identity & Physical Properties
Colorless to slightly yellow liquid with a pungent, acrid odor. Corrosive aqueous solution, typically 48-50% concentration in water.
| Also known as | Tetrafluoroboric acidBorofluoric acidHydrogen tetrafluoroborateFluoroborate |
| CAS Number | 16872-11-0 |
| Appearance | Colorless to slightly yellow liquid with a pungent, acrid odor. Corrosive aqueous solution, typically 48-50% concentration in water. |
| Flash Point | Not applicable (non-flammable aqueous solution) |
| Boiling Point | 130C (266F) for 48% solution; decomposes at higher temperatures |
| Vapor Density | Not applicable (aqueous solution, heavier than air vapors) |
| Water Reactivity | Soluble in water, releases heat when diluted; already an aqueous solution |
Fireground Response Guidance — UN 1775
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 1775 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 154, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 1775 — Fluoroboric acidUse 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.