☣️ UN 2601 • CLASS 2
UN 2601 — Cyclobutane
Placard: Flammable Gas. ERG Guide 115. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
🚒☣️
⚠️ This page is a quick-reference aid. For real incidents: stage upwind, isolate, deny entry, request Hazmat early, and consult the current ERG + SOP/SOG.
Advertisement
UN 2601 Quick Details
UN 2601
Product name: Cyclobutane
DOT Class: 2
Placard type: Flammable Gas
ERG Guide: 115 (check current ERG)
Initial isolation: ERG 115: isolate 100m all directions initially; evacuate 800m downwind if tank/rail car involved in fire
Common Hazards of UN 2601
- EXTREMELY FLAMMABLE.
- Will be easily ignited by heat, sparks or flames.
- Will form explosive mixtures with air.
- Vapors from liquefied gas are initially heavier than air and spread along ground.
- Vapors may travel to source of ignition and flash back.
- Cylinders exposed to fire may vent and release flammable gas through pressure relief devices.
- Containers may explode when heated.
- Ruptured cylinders may rocket.
Chemical Identity & Physical Properties
| Also known as | TetramethyleneCyclobutane gasCB |
| CAS Number | 287-23-0 |
| Appearance | Colorless gas with a mild petroleum-like odor. Exists as a compressed liquefied gas under pressure at room temperature. |
| Flash Point | -10C (14F) |
| Boiling Point | 13C (55F) |
| Vapor Density | 1.9 (heavier than air) |
| Water Reactivity | No significant reaction with water |
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Fireground Response Guidance — UN 2601
Extinguishing Media
Dry chemical, CO2, water spray for cooling containers only
PPE Requirements
⚠️ Level B minimum with SCBA; full protective clothing for fire situations
Isolation & Evacuation
ERG 115: isolate 100m all directions initially; evacuate 800m downwind if tank/rail car involved in fire
Always confirm protective actions with the current edition of the Emergency Response Guidebook (ERG Guide 115).
First Actions for a UN 2601 Incident
- CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Many gases are heavier than air and will spread along the ground and collect in low or confined areas
- Isolate spill or leak area for at least 100 meters (330 feet) in all directions.
- Consider initial downwind evacuation for at least 800 meters (1/2 mile).
Advertisement
📋 Copy & Share Field Card
UN 2601 — CyclobutaneHAZMAT RADIO NOTE — UN 2601
Product: Cyclobutane
Class 2 / Flammable Gas / ERG 115
PPE: Level B minimum with SCBA; full protective clothing for fire situations
ISOLATION: ERG 115: isolate 100m all directions initially; evacuate 800m downwind if tank/rail car involved in fire
ACTION: Stage upwind · Isolate · Deny entry · Request HazmatRADIO
Use for: Quick radio or face-to-face size-up. Short, structured, field-ready.
=== IC HAZMAT BRIEFING ===
UN 2601 — Cyclobutane
Class: 2 | Placard: Flammable Gas | ERG Guide: 115
Appearance: Colorless gas with a mild petroleum-like odor. Exists as a compressed liquefied gas under pressure at room temperature.
Water Reactivity: No significant reaction with water
Extinguishing: Dry chemical, CO2, water spray for cooling containers only
PPE: Level B minimum with SCBA; full protective clothing for fire situations
Isolation: ERG 115: isolate 100m all directions initially; evacuate 800m downwind if tank/rail car involved in fire
— Key Hazards —
• EXTREMELY FLAMMABLE.
• Will be easily ignited by heat, sparks or flames.
• Will form explosive mixtures with air.
— First Actions —
• CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper
• Keep unauthorized personnel away.
• Stay upwind, uphill and/or upstream.
• Many gases are heavier than air and will spread along the ground and collect in low or confined areas
SOURCE: allfirefighter.com/hazmat/un/2601 | Always use current ERG + SOP/SOGIC BRIEFING
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief. Full chemical + response details.
UN2601 Cyclobutane Cls2 ERG115 | ERG 115: isolate 100m all directions initially; evacuate 800m downwind if tank/r | allfirefighter.com/hazmat/un/2601SMS / 160 CHAR
Use for: Quick text to command or incoming units. Fits in a single SMS. Includes link to full page.
⚠️ Quick-reference only. Always use current ERG + SOP/SOG for incident-specific actions.
Page: https://allfirefighter.com/hazmat/un/2601
Advertisement
Frequently Asked Questions about UN 2601
EXTREMELY FLAMMABLE. Will be easily ignited by heat, sparks or flames. Will form explosive mixtures with air. Vapors from liquefied gas are initially heavier than air and spread along ground. Vapors may travel to source of ignition and flash back. Cylinders exposed to fire may vent and release flammable gas through pressure relief devices. Containers may explode when heated. Ruptured cylinders may rocket.
CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper Keep unauthorized personnel away. Stay upwind, uphill and/or upstream.
Level B minimum with SCBA; full protective clothing for fire situations
Water reactivity: No significant reaction with water. Recommended extinguishing: Dry chemical, CO2, water spray for cooling containers only.
ERG Guide 115 recommendation: ERG 115: isolate 100m all directions initially; evacuate 800m downwind if tank/rail car involved in fire
No. This is a training/quick-reference aid only. Always consult the current ERG Guide 115 and your department SOP/SOG for incident-specific protective actions.
Sources (high level): DOT/PHMSA marking & class concepts + ERG usage principles.
This page does not reproduce ERG guide text—always consult the current ERG for incident-specific protective actions.