UN 1746 — Bromine trifluoride
Placard: Oxidizer. ERG Guide 144. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1746 is Bromine trifluoride, a strong oxidizing interhalogen liquid assigned to ERG Guide 144. It is highly corrosive and reacts violently with water, releasing toxic fluoride and bromide fumes.
Hazard overview: UN 1746 presents oxidizer, water-reactive, toxic fume and corrosive liquid hazards. It can ignite combustibles, react with common materials and create severe HF/HBr-type exposure risks.
Response guidance: For a UN 1746 incident, responders should verify the product with shipping papers, package markings, SDS and ERG Guide 144. 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 1746 should emphasize interhalogen oxidizer behavior, violent water reaction, HF/HBr/HCl fume hazards, incompatible materials, withdrawal decisions and dry-agent limitations. Use ERG 144, SDS and hazmat SOP.
Regulatory context: Bromine trifluoride is regulated as a hazardous material for transportation and emergency response purposes. Transportation, workplace exposure, spill reporting, waste handling, storage and environmental requirements may vary by concentration, formulation, 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: Bromine trifluoride should be stored in compatible pressure or corrosion-resistant containers under strict oxidizer/reactive-material controls, away from water, fuels, organics, reducing agents, metals where incompatible, heat and unauthorized access. Storage should follow SDS, facility hazmat engineering controls and emergency planning.
UN 1746 Quick Details
Common Hazards of UN 1746
- STRONG OXIDIZER and highly corrosive interhalogen compound.
- May ignite combustibles such as wood, paper, oil, clothing, packaging and contaminated absorbents.
- Reacts violently or explosively with water, releasing toxic and corrosive hydrogen fluoride and hydrogen bromide fumes.
- Can react dangerously with fuels, organic materials, metals, reducing agents and many common materials.
- Vapors are heavy and irritating and may collect in low or confined areas.
- Containers may rupture or explode when heated.
- Runoff may create fire, explosion, toxic and corrosive contamination hazards.
Chemical Identity & Physical Properties
Colorless to pale yellow fuming liquid with a pungent, irritating odor. Highly reactive and corrosive. Hydrolyzes violently in moist air producing dense white fumes.
| Also known as | Bromine fluorideBrF3TrifluorobromineBromine(III) fluoride |
| CAS Number | 7787-71-5 |
| Appearance | Colorless to pale yellow fuming liquid with a pungent, irritating odor. Highly reactive and corrosive. Hydrolyzes violently in moist air producing dense white fumes. |
| Flash Point | Not applicable (strong oxidizer, not flammable itself) |
| Boiling Point | 127°C (261°F) |
| Vapor Density | 4.8 (much heavier than air) |
| Water Reactivity | Reacts violently and explosively with water, producing toxic and corrosive hydrogen fluoride and hydrogen bromide gases. Never use water directly. |
Fireground Response Guidance — UN 1746
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA and chemical protective clothing selected by hazmat specialists. Level A may be needed for close entry, unknown concentrations or liquefied gas/vapor contact because toxic, corrosive and heavy-vapor hazards may be severe.
Isolation & Evacuation
First Actions for a UN 1746 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 gas and avoid skin or eye contact.
- Keep fuels, organics, reducing agents and contaminated absorbents away from the material.
- Keep water and moisture away from released product unless incident command confirms a compatible cooling or control use.
- 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, gas, dust, fire involvement, water reaction or unknown concentration is present.
- Use ERG Guide 144, shipping papers, SDS, air monitoring and incident command for protective actions.
📋 Copy & Share Field Card
UN 1746 — Bromine trifluorideUse 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.