UN 2505 — Ammonium fluoride
Placard: Toxic. ERG Guide 154. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2505 is Ammonium fluoride, a toxic corrosive fluoride salt assigned to ERG Guide 154. Water can create acidic fluoride solution.
Hazard overview: TOXIC and CORROSIVE fluoride salt; inhalation, ingestion or skin contact may cause severe injury. Dissolves in water to form acidic fluoride solution with hydrogen-fluoride-type burn risk. Dust or solution can burn eyes, skin and respiratory tissue.
Response guidance: For UN 2505, isolate the area, avoid skin contact and use SCBA where vapor, dust, mist or fire is present. Contain toxic/corrosive runoff and verify product controls with SDS and ERG 154.
Firefighter training notes: Training for UN 2505 should emphasize toxic/corrosive exposure routes, skin absorption, SCBA use, decontamination, runoff containment and SDS verification. Use ERG 154, SDS and local SOP.
Regulatory context: Ammonium fluoride is regulated as a hazardous material for transport and emergency response. Storage, exposure, spill reporting, waste and fire-code duties depend on quantity, concentration and jurisdiction; verify shipping papers, SDS and local authority requirements.
Storage & handling: Ammonium fluoride should be stored in tightly closed compatible containers with ventilation, secondary containment, restricted access and SDS-based segregation from incompatible materials.
UN 2505 Quick Details
Common Hazards of UN 2505
- TOXIC and CORROSIVE fluoride salt; inhalation, ingestion or skin contact may cause severe injury.
- Dissolves in water to form acidic fluoride solution with hydrogen-fluoride-type burn risk.
- Dust or solution can burn eyes, skin and respiratory tissue.
- Non-combustible, but heating can release ammonia and corrosive fluoride fumes.
- Contact with some metals may generate flammable hydrogen gas under acidic conditions.
- Runoff may be fluoride-contaminated and harmful to waterways.
- Calcium-compatible medical/decon planning may be needed for fluoride exposure.
Chemical Identity & Physical Properties
White crystalline solid or colorless to white powder. Odorless or slight ammonia-like odor. Hygroscopic and may form lumps when exposed to moisture.
| Also known as | Neutral ammonium fluorideAmmonium fluoride solutionAmflorFluorid amonny |
| CAS Number | 12125-01-8 |
| Appearance | White crystalline solid or colorless to white powder. Odorless or slight ammonia-like odor. Hygroscopic and may form lumps when exposed to moisture. |
| Flash Point | Not applicable (non-flammable inorganic salt) |
| Boiling Point | Not applicable (decomposes at approximately 238C/460F) |
| Vapor Density | Not applicable (solid material) |
| Water Reactivity | Soluble in water forming acidic solution; no violent reaction but generates heat and potentially corrosive/toxic fumes |
Fireground Response Guidance — UN 2505
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA and chemical-resistant protective clothing. Level A may be needed for heavy fuming, splash risk or unknown concentrations.
Isolation & Evacuation
First Actions for a UN 2505 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 or spilled material without proper training and PPE.
- Prevent contaminated dust, liquid, runoff and decontamination waste from spreading.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 154, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 2505 — Ammonium fluorideUse 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.