UN 2642 — Fluoroacetic acid
Placard: Toxic. ERG Guide 154. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2642 is Fluoroacetic acid, a highly toxic corrosive acid assigned to ERG Guide 154. Dust, acidic solution and skin absorption must be controlled.
Hazard overview: HIGHLY TOXIC and CORROSIVE acid; inhalation, ingestion or skin absorption may be fatal. Dust, molten material or solution can burn eyes, skin and respiratory tissue. Dissolves in water to form a highly toxic acidic solution; no violent water reaction is expected.
Response guidance: For UN 2642, isolate the area, avoid skin contact and use SCBA where dust, vapor, mist or fire is present. Prevent spread of contaminated runoff, cool containers from protection and verify controls with SDS and ERG 154.
Firefighter training notes: Training for UN 2642 should emphasize toxic exposure routes, skin absorption, SCBA use, dust/vapor control, decontamination, runoff containment and SDS verification. Use ERG 154, SDS and local SOP.
Regulatory context: Fluoroacetic acid 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: Fluoroacetic acid should be stored in tightly closed compatible containers with ventilation, secondary containment, restricted access and SDS-based segregation from incompatible materials.
UN 2642 Quick Details
Common Hazards of UN 2642
- HIGHLY TOXIC and CORROSIVE acid; inhalation, ingestion or skin absorption may be fatal.
- Dust, molten material or solution can burn eyes, skin and respiratory tissue.
- Dissolves in water to form a highly toxic acidic solution; no violent water reaction is expected.
- Non-flammable solid, but heating or fire may produce toxic fluoride-containing fumes.
- Contact with metals may generate flammable hydrogen under acidic conditions.
- Runoff may be acidic, toxic and environmentally harmful.
- Avoid dust generation, skin contact and contaminated clothing exposure.
Chemical Identity & Physical Properties
Colorless to white crystalline solid at room temperature. Odorless or faint acetic acid-like odor. Highly toxic metabolic poison.
| Also known as | Monofluoroacetic acidFluoroethanoic acidMFACompound 1080 (related)2-Fluoroacetic acid |
| CAS Number | 144-49-0 |
| Appearance | Colorless to white crystalline solid at room temperature. Odorless or faint acetic acid-like odor. Highly toxic metabolic poison. |
| Flash Point | Not applicable (non-flammable solid) |
| Boiling Point | 165C (329F) |
| Vapor Density | Not applicable (solid at ambient temperature) |
| Water Reactivity | Soluble in water; no violent reaction but dissolved material is highly toxic |
Fireground Response Guidance — UN 2642
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA and full chemical protective clothing. Level A may be needed for heavy vapor, dust, splash risk or unknown concentrations; prevent all skin contact.
Isolation & Evacuation
First Actions for a UN 2642 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 2642 — Fluoroacetic 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.