UN 2552 — Hexafluoroacetone hydrate, liquid
Placard: Toxic. ERG Guide 151. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
Hexafluoroacetone hydrate is a highly toxic liquid shipped as UN 2552. Responders should treat vapor, liquid contact and contaminated runoff as serious exposure hazards.
Hazard overview: Exposure by inhalation, ingestion or skin absorption may be fatal. Heating can generate corrosive and toxic decomposition products, and the liquid can contaminate runoff or equipment.
Response guidance: Isolate the area, keep personnel upwind and avoid contact with liquid or vapor. Use compatible extinguishing agents for surrounding fires and water spray for cooling only when it does not spread contamination.
Firefighter training notes: Train crews on toxic liquid absorption hazards, decon setup and contaminated runoff control. Stress that odor is not a safe exposure indicator.
Regulatory context: UN 2552 is transported as Hexafluoroacetone hydrate, liquid, Class 6 toxic material. Verify exact concentration and emergency contact information on shipping papers.
Storage & handling: Store tightly closed in a cool, ventilated toxic-material area with secondary containment. Keep away from heat and incompatible materials.
UN 2552 Quick Details
Common Hazards of UN 2552
- Hexafluoroacetone hydrate is highly toxic; inhalation, ingestion or skin absorption may be fatal.
- Liquid and vapor can irritate or burn skin, eyes and respiratory tract.
- Heating or fire may produce corrosive and toxic decomposition products.
- Containers can rupture when heated.
- Runoff from spill control or fire operations may be toxic and environmentally harmful.
- Vapor may collect in low or confined areas because it is heavier than air.
- Water contact does not remove the toxicity; contaminated liquid remains hazardous.
Chemical Identity & Physical Properties
Hexafluoroacetone hydrate is a colorless to pale yellow liquid with a pungent irritating odor. It can fume and absorb moisture from air.
| Also known as | HFA hydrate1,1,1,3,3,3-hexafluoroacetone hydratehexafluoropropanone hydratehexafluoroacetone monohydrate |
| CAS Number | 34202-69-2 |
| Appearance | Colorless to pale yellow liquid with a pungent, irritating odor. Fuming liquid that absorbs moisture from air. |
| Flash Point | Not applicable (non-flammable) |
| Boiling Point | 106C (223F) |
| Vapor Density | 5.2 (heavier than air) |
| Water Reactivity | Miscible with water; hydrolyzes slowly releasing hexafluoroacetone |
Fireground Response Guidance — UN 2552
Extinguishing Media
PPE Requirements
Use SCBA and full chemical protective clothing. Level A may be needed where vapor concentration is unknown or skin absorption risk is high.
Isolation & Evacuation
First Actions for a UN 2552 Incident
- Call 911 and the emergency response number on the shipping papers.
- Keep unauthorized personnel away and isolate from an upwind position.
- Stay upwind, uphill and upstream of vapor, liquid and runoff.
- Avoid breathing vapor and avoid all skin or eye contact.
- Do not touch damaged containers or spilled liquid without full chemical PPE.
- Ventilate confined spaces only with trained hazmat entry, SCBA and monitoring.
- Use ERG 151, SDS and shipping papers to confirm isolation, decon and medical actions.
📋 Copy & Share Field Card
UN 2552 — Hexafluoroacetone hydrate, liquidUse 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.