☣️ UN 1058 • CLASS 2

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.

🚒☣️
⚠️ 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.

UN 1058 is Liquefied gases, nonflammable, charged with nitrogen, carbon dioxide or air, a Class 2 flammable gas assigned to ERG Guide 120. It can form explosive vapor-air mixtures, create flashback hazards and involve pressure containers that may rupture when heated.

Hazard overview: UN 1058 presents flammable vapor, flashback and pressure-container hazards. Released gas may migrate before ignition, and fire or heat can cause cylinders, tanks or relief devices to vent, rupture or rocket.

Response guidance: For a UN 1058 incident, responders should confirm the product using shipping papers, cylinder markings, SDS and ERG Guide 120. Establish incident command, isolate the area, stay upwind, eliminate ignition sources when safe, monitor for flammable gas and cool exposed containers from a protected position.

Firefighter training notes: Training for UN 1058 should emphasize flammable vapor behavior, flashback, low-area migration, cylinder heating, relief-device hazards and ignition control. Common errors include approaching through vapor, operating damaged valves, standing near cylinder ends and underestimating explosion potential in confined spaces. Use ERG 120, gas monitoring and local SOP.

Regulatory context: Liquefied gases, nonflammable, charged with nitrogen, carbon dioxide or air is regulated as a hazardous material for transportation and emergency response purposes. Cylinder, workplace exposure, storage, reporting and environmental requirements may vary by product, quantity and jurisdiction. Responders should verify current requirements through shipping papers, SDS, cylinder markings, facility documents and applicable DOT, OSHA, EPA, NFPA, state or local authority guidance.

Storage & handling: Liquefied gases, nonflammable, charged with nitrogen, carbon dioxide or air cylinders or containers should be stored secured, well ventilated and away from heat, ignition sources, oxidizers, incompatible gases and physical damage. Storage areas should control leaks, cylinder impact, unauthorized access and accumulation of gas in low or confined spaces.

Advertisement

UN 1058 Quick Details

UN 1058
Product name: Liquefied gases, nonflammable, charged with nitrogen, carbon dioxide or air
DOT Class: 2
Placard type: Non-Flammable Gas
ERG Guide: 120 (check current ERG)
Initial isolation: ERG 120: Initial isolation 100m all directions; if tank/rail car involved in fire, isolate 800m all directions and consider evacuation for 800m in all directions

Common Hazards of UN 1058

  • EXTREMELY FLAMMABLE: will be easily ignited by heat, sparks or flames.
  • Will form explosive mixtures with air.
  • Vapors from liquefied gas may spread along the ground and collect in low or confined areas.
  • Vapors may travel to an ignition source and flash back.
  • Cylinders or pressure containers may vent, rupture or rocket when heated.
  • Liquefied gas contact may cause frostbite or cold burns.
  • Released gas can create a wide flammable atmosphere around damaged cylinders, valves or piping.

Chemical Identity & Physical Properties

Colorless, odorless liquefied gas mixture under pressure. Typically exists as liquid in cylinders but rapidly vaporizes to gas at atmospheric pressure and room temperature.

Also known asCompressed gas mixtureInert gas mixtureNon-flammable gas blendPressurized inert gas
AppearanceColorless, odorless liquefied gas mixture under pressure. Typically exists as liquid in cylinders but rapidly vaporizes to gas at atmospheric pressure and room temperature.
Flash PointNot applicable (non-flammable compressed gas)
Boiling PointVariable depending on mixture composition; typically -196°C to -78°C (-321°F to -108°F) for nitrogen/CO2 blends
Vapor DensityInitially heavier than air when released (typically 1.0-1.5), though warming gases may approach air density
Water ReactivityNo significant reaction with water
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.

Fireground Response Guidance — UN 1058

Extinguishing Media

Dry chemical or CO2 may be used for small gas fires if the gas supply can be shut off; water spray is mainly for cooling exposed cylinders or tanks from a protected position.

PPE Requirements

⚠️ Level C minimum in well-ventilated areas; Level B with SCBA in confined spaces due to asphyxiation hazard; insulated gloves required for cryogenic contact protection

Use positive-pressure SCBA for fire, leak, vapor cloud or confined-space operations. Structural firefighting gear may protect against fire conditions, but responders should maintain distance from heated cylinders and follow incident command and local SOP.

Isolation & Evacuation

ERG 120: Initial isolation 100m all directions; if tank/rail car involved in fire, isolate 800m all directions and consider evacuation for 800m in all directions
Always confirm protective actions with the current edition of the Emergency Response Guidebook (ERG Guide 120).

First Actions for a UN 1058 Incident

  • CALL 911. Then call the emergency response telephone number on the shipping paper, if available.
  • Keep unauthorized personnel away.
  • Stay upwind, uphill and/or upstream.
  • Do not touch damaged cylinders, tanks, valves or released material unless properly trained and equipped.
  • Eliminate ignition sources if it is safe to do so.
  • Many vapors from liquefied gas may spread along the ground and collect in low or confined areas.
  • Isolate the spill or leak area for at least 100 meters (330 feet) in all directions.
  • Consider initial evacuation for at least 800 meters (1/2 mile) for a large release, fire or heated container.
  • Use ERG Guide 120, shipping papers, SDS, gas monitoring and incident command to set protective actions.
Advertisement

📋 Copy & Share Field Card

UN 1058 — Liquefied gases, nonflammable, charged w
HAZMAT RADIO NOTE — UN 1058 Product: Liquefied gases, nonflammable, charged with nitrogen, carbon dioxide or air Class 2 / Non-Flammable Gas / ERG 120 PPE: Level C minimum in well-ventilated areas; Level B with SCBA in confined spaces due to asphyxiation hazard; insulated gloves required for cryogenic contact protection ISOLATION: ERG 120: Initial isolation 100m all directions; if tank/rail car involved in fire, isolate 800m all directions and consider evacuation for 800m in all directions ACTION: Stage upwind · Isolate · Deny entry · Request HazmatRADIO

Use for: Quick radio or face-to-face size-up. Short, structured, field-ready.

SMS WhatsApp
=== IC HAZMAT BRIEFING === UN 1058 — Liquefied gases, nonflammable, charged with nitrogen, carbon dioxide or air Class: 2 | Placard: Non-Flammable Gas | ERG Guide: 120 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. Water Reactivity: No significant reaction with water Extinguishing: Dry chemical or CO2 may be used for small gas fires if the gas supply can be shut off; water spray is mainly for cooling exposed cylinders or tanks from a protected position. PPE: Level C minimum in well-ventilated areas; Level B with SCBA in confined spaces due to asphyxiation hazard; insulated gloves required for cryogenic contact protection Isolation: ERG 120: Initial isolation 100m all directions; if tank/rail car involved in fire, isolate 800m all directions and consider evacuation for 800m in all directions — Key Hazards — • EXTREMELY FLAMMABLE: will be easily ignited by heat, sparks or flames. • Will form explosive mixtures with air. • Vapors from liquefied gas may spread along the ground and collect in low or confined areas. — First Actions — • CALL 911. Then call the emergency response telephone number on the shipping paper, if available. • Keep unauthorized personnel away. • Stay upwind, uphill and/or upstream. • Do not touch damaged cylinders, tanks, valves or released material unless properly trained and equipped. SOURCE: allfirefighter.com/hazmat/un/liquefied-gases-nonflammable-charged-un-1058 | Always use current ERG + SOP/SOGIC BRIEFING

Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief.

SMS (short)
UN1058 Liquefied gases, nonflammable, charged with nitrogen, carbon dioxide or air Cls2 ERG120 | allfirefighter.com/hazmat/un/liquefied-gases-nonflammable-charged-un-1058SMS / 160 CHAR

Use for: Quick text to command or incoming units. Fits in a single SMS.

⚠️ Quick-reference only. Always use current ERG + SOP/SOG for incident-specific actions. Page: https://allfirefighter.com/hazmat/un/liquefied-gases-nonflammable-charged-un-1058

Related UN Numbers in Class 2

Discovery block for training / quick reference. Always consult the current ERG + your SOP/SOG for operations.
Advertisement

Frequently Asked Questions about UN 1058

UN 1058 is Liquefied gases, nonflammable, charged with nitrogen, carbon dioxide or air, a hazardous material assigned to ERG Guide 120.

Yes. It is a flammable gas that can form explosive mixtures with air.

ERG Guide 120 applies to UN 1058 and should be used for initial isolation, protective actions and first response guidance.

UN 1058 presents flammable vapor, flashback and pressure-container hazards. Released gas may migrate before ignition, and fire or heat can cause cylinders, tanks or relief devices to vent, rupture or rocket.

Use positive-pressure SCBA for fire, leak, vapor cloud or confined-space operations. Structural firefighting gear may protect against fire conditions, but responders should maintain distance from heated cylinders and follow incident command and local SOP.

Responders should isolate the area, stay upwind, verify the product with shipping papers and SDS, use ERG Guide 120, monitor the atmosphere when possible and follow incident command and local SOP.
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.