UN 1018 — Chlorodifluoromethane
Placard: Non-Flammable Gas. ERG Guide 126. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
Chlorodifluoromethane is a colorless gas with a faint, sweetish odor, shipped as a liquefied compressed gas under its own vapor pressure. It is used in various industrial applications, but requires careful handling due to its potential hazards.
Hazard overview: Chlorodifluoromethane is a non-flammable gas, but some may burn, and containers may explode when heated, posing a significant threat to people and property. It can also cause frostbite and other cold-related injuries if not handled properly.
Response guidance: In case of a chlorodifluoromethane leak, isolate the area immediately, and protect from heat and fire sources. Use water spray to cool containers, and wear Level B minimum protective equipment, including SCBA and thermal gloves for frostbite protection.
UN 1018 Quick Details
Common Hazards of UN 1018
- Some may burn but none ignite readily.
- Containers may explode when heated.
- Ruptured cylinders may rocket.
- Vapors may cause dizziness or asphyxiation without warning, especially when in closed or confined areas.
- Vapors from liquefied gas are initially heavier than air and spread along ground.
- Contact with gas or liquefied gas may cause burns, severe injury and/or frostbite.
- Fire may produce irritating, corrosive and/or toxic gases.
Chemical Identity & Physical Properties
Chlorodifluoromethane is a colorless gas with a faint, sweetish odor, and does not react significantly with water.
| Also known as | HCFC-22R-22Freon 22DifluoromonochloromethaneCHClF2 |
| CAS Number | 75-45-6 |
| Appearance | Colorless gas with a faint, sweetish odor. Shipped as a liquefied compressed gas under its own vapor pressure. |
| Flash Point | Not applicable (non-flammable gas) |
| Boiling Point | -40.8C (-41.4F) |
| Vapor Density | 3.0 (heavier than air) |
| Water Reactivity | No significant reaction with water |
Fireground Response Guidance — UN 1018
Extinguishing Media
PPE Requirements
Level B minimum protective equipment, including SCBA and thermal gloves for frostbite protection, is required when handling chlorodifluoromethane in confined spaces or areas with potential for leaks.
Isolation & Evacuation
First Actions for a UN 1018 Incident
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Ventilate closed spaces before entering, but only if properly trained and equipped.
- Isolate spill or leak area for at least 100 meters (330 feet) in all directions.
- Consider initial downwind evacuation for at least 500 meters (1/3 mile).
📋 Copy & Share Field Card
UN 1018 — ChlorodifluoromethaneUse 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.