☣️ UN 3120 • CLASS 5
UN 3120 — Organic peroxide type F, solid, temperature controlled
Placard: Organic Peroxide. ERG Guide 148. 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.
Advertisement
UN 3120 Quick Details
UN 3120
Product name: Organic peroxide type F, solid, temperature controlled
DOT Class: 5
Placard type: Organic Peroxide
ERG Guide: 148 (check current ERG)
Initial isolation: ERG 148: isolate spill area immediate 25m all directions; if tank/railcar/trailer involved in fire isolate 800m all directions and consider initial evacuation 800m all directions
Common Hazards of UN 3120
- May explode from heat, contamination or loss of temperature control.
- These materials are particularly sensitive to temperature rises. Above a given "Control Temperature"
- May ignite combustibles (wood, paper, oil, clothing, etc.).
- May ignite spontaneously if exposed to air.
- May be ignited by heat, sparks or flames.
- May burn rapidly with flare-burning effect.
- Containers may explode when heated.
- Runoff may create fire or explosion hazard.
Chemical Identity & Physical Properties
| Also known as | Temperature controlled organic peroxide solidSelf-reactive solid type FOrganic peroxide SADT solidTemperature sensitive peroxide solid |
| Appearance | Solid material of varying color depending on specific compound. Generally white to off-white powder or granular solid. May be odorless or have a slight characteristic odor. Requires temperature control during transport. |
| Flash Point | Not applicable (self-reactive/explosive material) |
| Boiling Point | Not applicable (decomposes before boiling) |
| Vapor Density | Not applicable (solid) |
| Water Reactivity | Generally no violent reaction with water, but water may cause decomposition or accelerate thermal instability in some formulations |
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Fireground Response Guidance — UN 3120
Extinguishing Media
Water spray to cool containers only; dry chemical or CO2 for small fires; do not use foam on material itself
PPE Requirements
⚠️ Level B minimum with full face SCBA required; structural firefighter protective clothing provides limited protection; maintain safe distance due to explosion potential
Isolation & Evacuation
ERG 148: isolate spill area immediate 25m all directions; if tank/railcar/trailer involved in fire isolate 800m all directions and consider initial evacuation 800m all directions
Always confirm protective actions with the current edition of the Emergency Response Guidebook (ERG Guide 148).
First Actions for a UN 3120 Incident
- CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters
- Consider initial evacuation for at least 250 meters (800 feet) in all directions.
Advertisement
📋 Copy & Share Field Card
UN 3120 — Organic peroxide type F, solid, temperatHAZMAT RADIO NOTE — UN 3120
Product: Organic peroxide type F, solid, temperature controlled
Class 5 / Organic Peroxide / ERG 148
PPE: Level B minimum with full face SCBA required; structural firefighter protective clothing provides limited protection; maintain safe distance due to explosion potential
ISOLATION: ERG 148: isolate spill area immediate 25m all directions; if tank/railcar/trailer involved in fire isolate 800m all directions and consider initial evacuation 800m all directions
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 3120 — Organic peroxide type F, solid, temperature controlled
Class: 5 | Placard: Organic Peroxide | ERG Guide: 148
Appearance: Solid material of varying color depending on specific compound. Generally white to off-white powder or granular solid. May be odorless or have a slight characteristic odor. Requires temperature control during transport.
Water Reactivity: Generally no violent reaction with water, but water may cause decomposition or accelerate thermal instability in some formulations
Extinguishing: Water spray to cool containers only; dry chemical or CO2 for small fires; do not use foam on material itself
PPE: Level B minimum with full face SCBA required; structural firefighter protective clothing provides limited protection; maintain safe distance due to explosion potential
Isolation: ERG 148: isolate spill area immediate 25m all directions; if tank/railcar/trailer involved in fire isolate 800m all directions and consider initial evacuation 800m all directions
— Key Hazards —
• May explode from heat, contamination or loss of temperature control.
• These materials are particularly sensitive to temperature rises. Above a given "Control Temperature"
• May ignite combustibles (wood, paper, oil, clothing, etc.).
— First Actions —
• CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper
• Keep unauthorized personnel away.
• Stay upwind, uphill and/or upstream.
• Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters
SOURCE: allfirefighter.com/hazmat/un/3120 | Always use current ERG + SOP/SOGIC BRIEFING
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief. Full chemical + response details.
UN3120 Organic peroxide type F, solid, temperature controlled Cls5 ERG148 | allfirefighter.com/hazmat/un/3120SMS / 160 CHAR
Use for: Quick text to command or incoming units. Fits in a single SMS. Includes link to full page.
⚠️ Quick-reference only. Always use current ERG + SOP/SOG for incident-specific actions.
Page: https://allfirefighter.com/hazmat/un/3120
Advertisement
Frequently Asked Questions about UN 3120
May explode from heat, contamination or loss of temperature control. These materials are particularly sensitive to temperature rises. Above a given "Control Temperature" May ignite combustibles (wood, paper, oil, clothing, etc.). May ignite spontaneously if exposed to air. May be ignited by heat, sparks or flames. May burn rapidly with flare-burning effect. Containers may explode when heated. Runoff may create fire or explosion hazard.
CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper Keep unauthorized personnel away. Stay upwind, uphill and/or upstream.
Level B minimum with full face SCBA required; structural firefighter protective clothing provides limited protection; maintain safe distance due to explosion potential
Water reactivity: Generally no violent reaction with water, but water may cause decomposition or accelerate thermal instability in some formulations. Recommended extinguishing: Water spray to cool containers only; dry chemical or CO2 for small fires; do not use foam on material itself.
ERG Guide 148 recommendation: ERG 148: isolate spill area immediate 25m all directions; if tank/railcar/trailer involved in fire isolate 800m all directions and consider initial evacuation 800m all directions
No. This is a training/quick-reference aid only. Always consult the current ERG Guide 148 and your department SOP/SOG for incident-specific protective actions.
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.