UN 3057 — Trifluoroacetyl chloride
Placard: Toxic Gas. ERG Guide 125. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3057 At a Glance
UN 3057 (Trifluoroacetyl chloride) is listed as DOT Class 2 Toxic Gas and is assigned to ERG Guide 125. Use this page to review placard data, common hazards, PPE notes, isolation context, first actions, and related UN numbers.
UN 3057 is Trifluoroacetyl chloride, a toxic corrosive liquefied acid chloride gas assigned to ERG Guide 125. Moisture reaction and low-area vapor are key hazards.
Hazard overview: TOXIC and CORROSIVE liquefied acid chloride gas; inhalation may be fatal. Reacts violently with water or moist air, releasing hydrogen chloride, hydrogen fluoride-containing products and heat. Gas or liquefied gas can burn eyes, skin and respiratory tissue; liquefied gas may also cause frostbite.
Response guidance: For UN 3057, isolate downwind/low areas, use SCBA with chemical protection and cool cylinders from a protected position. Control reactive/corrosive runoff under ERG 125.
Firefighter training notes: Training for UN 3057 should emphasize exposure routes, SCBA use, vapor/dust monitoring, decontamination, runoff containment and SDS/package verification. Use ERG 125, SDS and local SOP.
Regulatory context: Trifluoroacetyl chloride is regulated as a hazardous material for transport and emergency response. Storage, reporting, exposure, waste and incident-notification duties depend on quantity, formulation and jurisdiction; verify shipping papers, SDS and authority guidance.
Storage & handling: Trifluoroacetyl chloride should be stored in tightly closed compatible containers with ventilation, secondary containment, restricted access and SDS-based segregation from incompatible materials.
UN 3057 Quick Details
Common Hazards of UN 3057
- TOXIC and CORROSIVE liquefied acid chloride gas; inhalation may be fatal.
- Reacts violently with water or moist air, releasing hydrogen chloride, hydrogen fluoride-containing products and heat.
- Gas or liquefied gas can burn eyes, skin and respiratory tissue; liquefied gas may also cause frostbite.
- Vapors from liquefied gas are initially heavier than air and can spread along the ground.
- Containers exposed to fire may vent, rupture or rocket.
- Fire may produce corrosive/toxic acid gases and fluorinated smoke.
- Runoff or vapor-control water may be acidic, fluoride-contaminated and toxic.
Chemical Identity & Physical Properties
Colorless to pale yellow fuming liquid with a pungent, acrid odor. Fumes heavily in moist air due to reaction with water vapor.
| Also known as | Trifluoroacetyl chlorideTFACTrifluoroacetic acid chlorideTrifluoroethanoyl chloride |
| CAS Number | 354-32-5 |
| Appearance | Colorless to pale yellow fuming liquid with a pungent, acrid odor. Fumes heavily in moist air due to reaction with water vapor. |
| Flash Point | Not applicable (non-flammable) |
| Boiling Point | -28C (-18F) |
| Vapor Density | 4.6 (heavier than air) |
| Water Reactivity | Reacts violently with water, producing corrosive hydrofluoric acid and trifluoroacetic acid vapors; do not use water directly on material |
Fireground Response Guidance — UN 3057
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA and fully encapsulating chemical protective clothing for significant releases. Protect against toxic corrosive gas and liquefied-gas frostbite.
Isolation & Evacuation
First Actions for a UN 3057 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, gas, mist, smoke or fumes and avoid skin or eye contact.
- Keep water or moisture contact controlled when it may increase fuming, heat or corrosive runoff.
- Do not touch damaged containers or spilled material without proper training and PPE.
- Prevent contaminated liquid, dust, runoff and decontamination waste from spreading.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 125, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 3057 — Trifluoroacetyl chlorideUse 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.