UN 2536 — Methyltetrahydrofuran
Placard: Flammable. ERG Guide 127. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 2536 is Methyltetrahydrofuran, a highly flammable ether assigned to ERG Guide 127. Flashback and possible peroxide/storage-history review are important.
Hazard overview: HIGHLY FLAMMABLE ether liquid; vapors may ignite easily and form explosive mixtures with air. Vapors are heavier than air and may travel to ignition sources and flash back. Vapor explosion hazard exists in drains, basements and confined areas.
Response guidance: For UN 2536, isolate the area, eliminate ignition sources, keep vapors out of drains and use SCBA in vapor or fire conditions. Select foam, dry chemical or CO2 using SDS and ERG 127.
Firefighter training notes: Training for UN 2536 should emphasize vapor travel, sewer flashback, foam selection, ignition control, container cooling, SCBA use and runoff containment. Use ERG 127, SDS and local SOP.
Regulatory context: Methyltetrahydrofuran 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: Methyltetrahydrofuran should be stored in approved compatible containers with ventilation, secondary containment and separation from heat, ignition sources, oxidizers and incompatible materials according to SDS.
UN 2536 Quick Details
Common Hazards of UN 2536
- HIGHLY FLAMMABLE ether liquid; vapors may ignite easily and form explosive mixtures with air.
- Vapors are heavier than air and may travel to ignition sources and flash back.
- Vapor explosion hazard exists in drains, basements and confined areas.
- Some ether materials can form explosive peroxides during storage; verify age, inhibitor status and SDS.
- Runoff to sewers may create fire or explosion hazards.
- Fire may produce carbon monoxide and irritating/toxic smoke.
- Containers may rupture or explode when heated.
Chemical Identity & Physical Properties
Clear, colorless liquid with a sweet, ether-like odor. Highly volatile solvent at room temperature.
| Also known as | 2-Methyltetrahydrofuran2-MeTHFSylvan |
| CAS Number | 96-47-9 |
| Appearance | Clear, colorless liquid with a sweet, ether-like odor. Highly volatile solvent at room temperature. |
| Flash Point | -11°C (12°F) |
| Boiling Point | 78-80°C (172-176°F) |
| Vapor Density | 3.0 (heavier than air) |
| Water Reactivity | Immiscible with water; no significant reaction but may form separate layer |
Fireground Response Guidance — UN 2536
Extinguishing Media
PPE Requirements
Use positive-pressure SCBA for vapor, fire or confined-space exposure. Wear chemical-resistant gloves, eye/face protection and flame-resistant protection as appropriate.
Isolation & Evacuation
First Actions for a UN 2536 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.
- Eliminate ignition sources if this can be done safely.
- 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.
- Ventilate confined spaces only after monitoring and only if properly trained and equipped.
- Use ERG Guide 127, SDS, shipping papers and monitoring to set isolation, evacuation and entry decisions.
📋 Copy & Share Field Card
UN 2536 — MethyltetrahydrofuranUse 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.