UN 2354 — Chloromethyl ethyl ether
Placard: Flammable. ERG Guide 131. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2354 is Chloromethyl ethyl ether, a toxic flammable chlorinated ether assigned to ERG Guide 131. Vapor flashback, skin exposure and corrosive decomposition products require strict control.
Hazard overview: TOXIC and FLAMMABLE chlorinated ether; inhalation, ingestion or skin absorption may cause severe injury. Vapors may ignite and form explosive mixtures with air. Moisture or water may hydrolyze material to acidic/corrosive products including hydrogen chloride and formaldehyde.
Response guidance: For UN 2354, isolate the release, remove ignition sources, stay upwind and use SCBA. Control water use because moisture can increase corrosive fuming; contain runoff and verify tactics with ERG 131, SDS and incident command.
Firefighter training notes: Training for UN 2354 should emphasize toxic vapor recognition, SCBA use, skin-contact prevention, sewer flashback, container cooling, decontamination and runoff control. Use ERG 131, SDS and local SOP.
Regulatory context: Chloromethyl ethyl ether 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: Chloromethyl ethyl ether should be stored in tightly closed compatible containers in a cool, dry, ventilated flammable/corrosive area away from moisture, heat, ignition sources, oxidizers and bases. Provide secondary containment.
UN 2354 Quick Details
Common Hazards of UN 2354
- TOXIC and FLAMMABLE chlorinated ether; inhalation, ingestion or skin absorption may cause severe injury.
- Vapors may ignite and form explosive mixtures with air.
- Moisture or water may hydrolyze material to acidic/corrosive products including hydrogen chloride and formaldehyde.
- Vapors are heavier than air and may travel to ignition sources and flash back.
- Fire may produce hydrogen chloride, phosgene-type gases and other toxic/corrosive smoke.
- Runoff to sewers may create fire, explosion and toxic/corrosive contamination hazards.
- Containers may rupture or explode when heated.
Chemical Identity & Physical Properties
Colorless to pale yellow liquid with a pungent, irritating odor. Volatile and flammable at room temperature.
| Also known as | Ethoxymethyl chlorideEther, chloromethyl ethyl1-Chloro-1-methoxyethaneEthyl chloromethyl ether |
| CAS Number | 3188-13-4 |
| Appearance | Colorless to pale yellow liquid with a pungent, irritating odor. Volatile and flammable at room temperature. |
| Flash Point | -23°C (-9°F) |
| Boiling Point | 83-85°C (181-185°F) |
| Vapor Density | 2.6 (heavier than air) |
| Water Reactivity | Slowly hydrolyzes in water producing hydrochloric acid and formaldehyde; avoid prolonged water contact |
Fireground Response Guidance — UN 2354
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for vapor, fire or confined-space exposure. Wear chemical-resistant gloves, boots, eye/face protection and protective clothing; avoid skin contact.
Isolation & Evacuation
First Actions for a UN 2354 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; keep responders out of low vapor areas.
- Eliminate ignition sources if this can be done safely.
- Avoid breathing vapor, mist or smoke and avoid skin or eye contact.
- Keep water contact limited and controlled because moisture can increase corrosive fuming.
- Do not touch damaged containers or spilled material without proper training and PPE.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 131, SDS, shipping papers and air monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 2354 — Chloromethyl ethyl etherUse 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.