☣️ UN 3187 • CLASS 4
UN 3187 — Self-heating liquid, poisonous, inorganic, n.o.s.
Placard: Spontaneously Combustible. ERG Guide 136. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
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⚠️ 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.
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UN 3187 Quick Details
UN 3187
Product name: Self-heating liquid, poisonous, inorganic, n.o.s.
DOT Class: 4
Placard type: Spontaneously Combustible
ERG Guide: 136 (check current ERG)
Initial isolation: ERG 136: isolate spill/leak area immediately 50m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and evacuate
Common Hazards of UN 3187
- Extremely flammable; will ignite itself if exposed to air.
- Burns rapidly, releasing dense, white, irritating fumes.
- Substance may be transported in a molten form.
- May re-ignite after fire is extinguished.
- Corrosives in contact with metals may evolve flammable hydrogen gas.
- Containers may explode when heated.
- Fire will produce irritating, corrosive and/or toxic gases.
- TOXIC and/or CORROSIVE; ingestion of substance or inhalation of decomposition products will cause
Chemical Identity & Physical Properties
| Also known as | Self-heating liquid, toxic, inorganic, n.o.s.Self-heating liquid, poisonous, inorganic, not otherwise specifiedClass 4.2 inorganic toxic liquid |
| Appearance | Variable appearance depending on specific substance; typically a liquid that may spontaneously heat and ignite when exposed to air at ambient temperatures, releasing dense white irritating fumes. |
| Flash Point | Not applicable (spontaneously combustible) |
| Boiling Point | Variable depending on specific chemical |
| Vapor Density | Variable depending on specific chemical |
| Water Reactivity | May react with water; consult shipping papers for specific chemical identity |
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Fireground Response Guidance — UN 3187
Extinguishing Media
Dry chemical, dry sand, soda ash; no water or foam on burning material
PPE Requirements
⚠️ Level A or B required; SCBA mandatory; full protective clothing due to toxic fumes and spontaneous ignition risk
Isolation & Evacuation
ERG 136: isolate spill/leak area immediately 50m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and evacuate
Always confirm protective actions with the current edition of the Emergency Response Guidebook (ERG Guide 136).
First Actions for a UN 3187 Incident
- CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper
- Stay upwind, uphill and/or upstream.
- Keep unauthorized personnel away.
- Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters
- For highlighted materials: see Table 1 - Initial Isolation and Protective Action Distances.
- For non-highlighted materials: increase the immediate precautionary measure distance, in the downwind
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📋 Copy & Share Field Card
UN 3187 — Self-heating liquid, poisonous, inorganiHAZMAT RADIO NOTE — UN 3187
Product: Self-heating liquid, poisonous, inorganic, n.o.s.
Class 4 / Spontaneously Combustible / ERG 136
PPE: Level A or B required; SCBA mandatory; full protective clothing due to toxic fumes and spontaneous ignition risk
ISOLATION: ERG 136: isolate spill/leak area immediately 50m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and evacuate
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 3187 — Self-heating liquid, poisonous, inorganic, n.o.s.
Class: 4 | Placard: Spontaneously Combustible | ERG Guide: 136
Appearance: Variable appearance depending on specific substance; typically a liquid that may spontaneously heat and ignite when exposed to air at ambient temperatures, releasing dense white irritating fumes.
Water Reactivity: May react with water; consult shipping papers for specific chemical identity
Extinguishing: Dry chemical, dry sand, soda ash; no water or foam on burning material
PPE: Level A or B required; SCBA mandatory; full protective clothing due to toxic fumes and spontaneous ignition risk
Isolation: ERG 136: isolate spill/leak area immediately 50m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and evacuate
— Key Hazards —
• Extremely flammable; will ignite itself if exposed to air.
• Burns rapidly, releasing dense, white, irritating fumes.
• Substance may be transported in a molten form.
— First Actions —
• CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper
• Stay upwind, uphill and/or upstream.
• Keep unauthorized personnel away.
• 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/3187 | Always use current ERG + SOP/SOGIC BRIEFING
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief. Full chemical + response details.
UN3187 Self-heating liquid, poisonous, inorganic, n.o.s. Cls4 ERG136 | allfirefighter.com/hazmat/un/3187SMS / 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/3187
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Frequently Asked Questions about UN 3187
Extremely flammable; will ignite itself if exposed to air. Burns rapidly, releasing dense, white, irritating fumes. Substance may be transported in a molten form. May re-ignite after fire is extinguished. Corrosives in contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. Fire will produce irritating, corrosive and/or toxic gases. TOXIC and/or CORROSIVE; ingestion of substance or inhalation of decomposition products will cause
CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper Stay upwind, uphill and/or upstream. Keep unauthorized personnel away.
Level A or B required; SCBA mandatory; full protective clothing due to toxic fumes and spontaneous ignition risk
Water reactivity: May react with water; consult shipping papers for specific chemical identity. Recommended extinguishing: Dry chemical, dry sand, soda ash; no water or foam on burning material.
ERG Guide 136 recommendation: ERG 136: isolate spill/leak area immediately 50m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and evacuate
No. This is a training/quick-reference aid only. Always consult the current ERG Guide 136 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.