☣️ UN 2857 • CLASS 2

UN 2857 — Refrigerating machines, containing non-flammable, non-poisonous gases

Placard: Non-Flammable Gas. ERG Guide 126. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.

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⚠️ 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.

Refrigerating machines, containing non-flammable, non-poisonous gases are equipment articles containing nonflammable, nonpoisonous refrigerant gas. The main response issues are pressure, asphyxiation, frostbite, and decomposition products in fire.

Hazard overview: An intact unit may pose little immediate hazard, but a leaking unit in a confined space can reduce oxygen without warning. Fire exposure can heat cylinders and produce irritating decomposition gases.

Response guidance: Isolate leaking or fire-exposed units, ventilate only with monitoring, and cool exposed containers from a protected position. Confirm the refrigerant type from the unit label or shipping documents.

Firefighter training notes: Training should cover refrigerant identification, oxygen monitoring, confined-space entry, frostbite precautions, ventilation, and cylinder-heating hazards for UN 2857.

Regulatory context: Confirm the equipment label, refrigerant type, SDS/service documentation, shipping papers, and ERG 126 before final response decisions.

Storage & handling: Keep units upright and protected from heat, impact, and puncture; ensure ventilation and do not store damaged leaking equipment in occupied spaces.

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UN 2857 Quick Details

UN 2857
Product name: Refrigerating machines, containing non-flammable, non-poisonous gases
DOT Class: 2
Placard type: Non-Flammable Gas
ERG Guide: 126 (check current ERG)
Initial isolation: ERG 126: No initial isolation required for small spills; for large spills or fire involvement, isolate 100m in all directions; evacuate area if containers are exposed to fire

Common Hazards of UN 2857

  • Contains compressed or liquefied nonflammable, nonpoisonous refrigerant gas.
  • Gas release can displace oxygen, especially in machinery rooms, vehicles, or confined spaces.
  • Liquefied gas contact can cause frostbite or cold burns.
  • Heated equipment or cylinders can rupture; ruptured cylinders may rocket.
  • Most refrigerant vapors are heavier than air and can collect near floors.
  • Fire can decompose some refrigerants into irritating or toxic gases.
  • Exact refrigerant type must be confirmed from labels, SDS, or service documents.

Chemical Identity & Physical Properties

Mechanical devices containing non-flammable, non-poisonous compressed gases (typically HFCs, HCFCs, or inert gases) as refrigerants. Equipment may be white, gray, or metallic in appearance

Also known asRefrigerator unitsCooling equipmentRefrigeration appliancesAir conditioning units with refrigerant
AppearanceMechanical devices containing non-flammable, non-poisonous compressed gases (typically HFCs, HCFCs, or inert gases) as refrigerants. Equipment may be white, gray, or metallic in appearance.
Flash PointNot applicable (non-flammable gases)
Boiling PointVaries by refrigerant gas used; typically -40C to -26C (-40F to -15F) for common refrigerants
Vapor DensityHeavier than air for most refrigerant gases (3-5 times 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 2857

Extinguishing Media

Not applicable; use water spray to cool containers if exposed to fire

PPE Requirements

⚠️ Level D for intact units; Level C with SCBA if gas leak occurs in confined space due to asphyxiation hazard

Intact units may require standard PPE. Use SCBA and atmospheric monitoring for leaks, fire exposure, confined spaces, or oxygen-deficient areas.

Isolation & Evacuation

ERG 126: No initial isolation required for small spills; for large spills or fire involvement, isolate 100m in all directions; evacuate area if containers are exposed to fire
Always confirm protective actions with the current edition of the Emergency Response Guidebook (ERG Guide 126).

First Actions for a UN 2857 Incident

  • Call 911 and the emergency response number shown on shipping papers or equipment documentation.
  • Keep unauthorized personnel away and isolate the release area.
  • Stay upwind and out of low or confined areas where refrigerant gas may displace oxygen.
  • Avoid direct contact with escaping gas or liquid refrigerant because frostbite injury is possible.
  • Do not enter machinery rooms, trailers, or confined spaces without SCBA and atmospheric monitoring.
  • Ventilate only after ignition, oxygen, and toxic decomposition hazards have been evaluated.
  • Use ERG 126, SDS/refrigerant label data, and monitoring results for final protective actions.
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📋 Copy & Share Field Card

UN 2857 — Refrigerating machines, containing non-f
HAZMAT RADIO NOTE — UN 2857 Product: Refrigerating machines, containing non-flammable, non-poisonous gases Class 2 / Non-Flammable Gas / ERG 126 PPE: Level D for intact units; Level C with SCBA if gas leak occurs in confined space due to asphyxiation hazard ISOLATION: ERG 126: No initial isolation required for small spills; for large spills or fire involvement, isolate 100m in all directions; evacuate area if containers are exposed to fire 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 2857 — Refrigerating machines, containing non-flammable, non-poisonous gases Class: 2 | Placard: Non-Flammable Gas | ERG Guide: 126 Appearance: Mechanical devices containing non-flammable, non-poisonous compressed gases (typically HFCs, HCFCs, or inert gases) as refrigerants. Equipment may be white, gray, or metallic in appearance. Water Reactivity: No significant reaction with water Extinguishing: Not applicable; use water spray to cool containers if exposed to fire PPE: Level D for intact units; Level C with SCBA if gas leak occurs in confined space due to asphyxiation hazard Isolation: ERG 126: No initial isolation required for small spills; for large spills or fire involvement, isolate 100m in all directions; evacuate area if containers are exposed to fire — Key Hazards — • Contains compressed or liquefied nonflammable, nonpoisonous refrigerant gas. • Gas release can displace oxygen, especially in machinery rooms, vehicles, or confined spaces. • Liquefied gas contact can cause frostbite or cold burns. — First Actions — • Call 911 and the emergency response number shown on shipping papers or equipment documentation. • Keep unauthorized personnel away and isolate the release area. • Stay upwind and out of low or confined areas where refrigerant gas may displace oxygen. • Avoid direct contact with escaping gas or liquid refrigerant because frostbite injury is possible. SOURCE: allfirefighter.com/hazmat/un/refrigerating-machines-containing-non-un-2857 | Always use current ERG + SOP/SOGIC BRIEFING

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

SMS (short)
UN2857 Refrigerating machines, containing non-flammable, non-poisonous gases Cls2 ERG126 | allfirefighter.com/hazmat/un/refrigerating-machines-containing-non-un-2857SMS / 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-non-un-2857

Related UN Numbers in Class 2

Discovery block for training / quick reference. Always consult the current ERG + your SOP/SOG for operations.
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Frequently Asked Questions about UN 2857

No. This entry is for nonflammable, nonpoisonous gas in refrigerating machines.

Oxygen displacement and asphyxiation, especially in confined or low areas.

Yes. Escaping liquefied refrigerant can cause cold burns or frostbite.

The exact refrigerant affects pressure, decomposition products, and ventilation decisions.

SCBA and atmospheric monitoring are needed for confined spaces or unknown gas levels.

Heated cylinders or components may rupture, and refrigerants can decompose into irritating gases.
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.