UN 1058 — Liquefied gases, nonflammable, charged with nitrogen, carbon dioxide or air
Placard: Non-Flammable Gas. ERG Guide 120. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 1058 Liquefied gases, nonflammable, charged with nitrogen, carbon dioxide, or air, are colorless, odorless, and can cause dizziness or asphyxiation without warning, especially in closed or confined areas. These gases are commonly used in various industrial applications, requiring careful handling and storage to prevent accidents.
Hazard overview: The vapors from these liquefied gases can cause dizziness or asphyxiation without warning, and are initially heavier than air, spreading along the ground and potentially leading to hazardous situations. Prolonged exposure to these vapors can also lead to health risks, emphasizing the need for caution when handling these substances.
Response guidance: In case of a spill or leak, it is essential to isolate the area immediately, using ERG 120 guidelines, and evacuate the surrounding area if necessary. Emergency responders should wear Level C minimum protective gear, including insulated gloves, to prevent exposure to the cryogenic temperatures and potential asphyxiation hazards.
UN 1058 Quick Details
Common Hazards of UN 1058
- 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, liquefied gas or cryogenic liquids may cause burns, severe injury and/or frostbite.
- Non-flammable gases.
- Containers may explode when heated.
- Ruptured cylinders may rocket.
Chemical Identity & Physical Properties
These liquefied gases are colorless, odorless, and exist as a liquid in cylinders, but rapidly vaporize to gas at atmospheric pressure and room temperature.
| Also known as | Compressed gas mixtureInert gas mixtureNon-flammable gas blendPressurized inert gas |
| Appearance | Colorless, odorless liquefied gas mixture under pressure. Typically exists as liquid in cylinders but rapidly vaporizes to gas at atmospheric pressure and room temperature. |
| Flash Point | Not applicable (non-flammable compressed gas) |
| Boiling Point | Variable depending on mixture composition; typically -196°C to -78°C (-321°F to -108°F) for nitrogen/CO2 blends |
| Vapor Density | Initially heavier than air when released (typically 1.0-1.5), though warming gases may approach air density |
| Water Reactivity | No significant reaction with water |
Fireground Response Guidance — UN 1058
Extinguishing Media
PPE Requirements
Emergency responders should wear Level C minimum protective gear, including insulated gloves, to prevent exposure to the cryogenic temperatures and potential asphyxiation hazards, and Level B with SCBA in confined spaces due to the asphyxiation hazard.
Isolation & Evacuation
First Actions for a UN 1058 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 100 meters (330 feet).
📋 Copy & Share Field Card
UN 1058 — Liquefied gases, nonflammable, charged wUse 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.