☣️ UN 3358 • CLASS 2
UN 3358 — Refrigerating machines, containing flammable, non-poisonous, liquefied gas
Placard: Flammable Gas. ERG Guide 115. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
🚒☣️
⚠️ Verification required:
Broad or variable material category; verify exact product, SDS and shipping papers.
⚠️ 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 3358 applies to refrigeration units or machinery containing flammable, non-poisonous liquefied gas refrigerants.
Hazard overview: If the sealed system leaks, flammable vapor can collect in low areas and ignite. Liquefied gas contact may cause frostbite.
Response guidance: Isolate the area, remove ignition sources, ventilate if safe and cool exposed machinery from a distance. Do not enter confined areas without SCBA.
Advertisement
UN 3358 Quick Details
UN 3358
Product name: Refrigerating machines, containing flammable, non-poisonous, liquefied gas
DOT Class: 2
Placard type: Flammable Gas
ERG Guide: 115 (check current ERG)
Initial isolation: ERG 115: isolate 100m all directions; if tank/container involved in fire, evacuate 800m radius
Common Hazards of UN 3358
- 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
Complete refrigeration units or machines containing flammable, non-toxic liquefied gases such as hydrocarbons (propane, isobutane) or ammonia refrigerants. Typically metal enclosures with compressor, condenser, and evaporator components.
| Also known as | Refrigerating machinesRefrigeration equipment containing flammable gasRefrigerant-containing appliancesCooling units with flammable refrigerant |
| Appearance | Complete refrigeration units or machines containing flammable, non-toxic liquefied gases such as hydrocarbons (propane, isobutane) or ammonia refrigerants. Typically metal enclosures with compressor, condenser, and evaporator components. |
| Flash Point | Not applicable (pressurized liquefied gas within sealed system) |
| Boiling Point | Varies by refrigerant: typically -42C to -12C (-44F to 10F) for common flammable refrigerants |
| Vapor Density | Heavier than air (most flammable refrigerants 1.5-2.0 relative to 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 3358
Extinguishing Media
Dry chemical, CO2, or water spray for cooling; avoid direct water on refrigerant leak
PPE Requirements
⚠️ Level B minimum if refrigerant leak suspected; SCBA required in enclosed spaces; thermal protection if fire involved
Use SCBA for leaks or fire. Wear thermal and cold-protection gloves if liquefied refrigerant contact is possible.
Isolation & Evacuation
ERG 115: isolate 100m all directions; if tank/container involved in fire, evacuate 800m radius
Always confirm protective actions with the current edition of the Emergency Response Guidebook (ERG Guide 115).
First Actions for a UN 3358 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.
- Many gases are heavier than air and may 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 3358 — Refrigerating machines, containing flammHAZMAT RADIO NOTE — UN 3358
Product: Refrigerating machines, containing flammable, non-poisonous, liquefied gas
Class 2 / Flammable Gas / ERG 115
PPE: Level B minimum if refrigerant leak suspected; SCBA required in enclosed spaces; thermal protection if fire involved
ISOLATION: ERG 115: isolate 100m all directions; if tank/container involved in fire, evacuate 800m radius
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 3358 — Refrigerating machines, containing flammable, non-poisonous, liquefied gas
Class: 2 | Placard: Flammable Gas | ERG Guide: 115
Appearance: Complete refrigeration units or machines containing flammable, non-toxic liquefied gases such as hydrocarbons (propane, isobutane) or ammonia refrigerants. Typically metal enclosures with compressor, condenser, and evaporator components.
Water Reactivity: No significant reaction with water
Extinguishing: Dry chemical, CO2, or water spray for cooling; avoid direct water on refrigerant leak
PPE: Level B minimum if refrigerant leak suspected; SCBA required in enclosed spaces; thermal protection if fire involved
Isolation: ERG 115: isolate 100m all directions; if tank/container involved in fire, evacuate 800m radius
— 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 the emergency response telephone number on the shipping paper, if available.
• Keep unauthorized personnel away.
• Stay upwind, uphill and/or upstream.
• Many gases are heavier than air and may collect in low or confined areas.
SOURCE: allfirefighter.com/hazmat/un/refrigerating-machines-containing-flammable-un-3358 | Always use current ERG + SOP/SOGIC BRIEFING
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief.
UN3358 Refrigerating machines, containing flammable, non-poisonous, liquefied gas Cls2 ERG115 | allfirefighter.com/hazmat/un/refrigerating-machines-containing-flammable-un-3358SMS / 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/refrigerating-machines-containing-flammable-un-3358
Advertisement
Frequently Asked Questions about UN 3358
UN 3358 is refrigerating machinery containing flammable, non-poisonous liquefied gas.
Yes. A refrigerant leak may form an ignitable vapor cloud.
Liquefied gas can cause frostbite on skin or eye contact.
Water spray may be used to cool exposed equipment, but avoid directing water into a refrigerant leak.
SCBA is needed for leaks or fire; cold-resistant gloves may be needed for liquefied gas exposure.
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.