☣️ UN 3185 • CLASS 4
UN 3185 — Self-heating liquid, corrosive, organic, 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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⚠️ 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.
Self-heating liquid, corrosive, organic, n.o.s. is a broad self-heating liquid entry. Product identity, packaging and temperature history control the response.
Hazard overview: The main risk is spontaneous heat buildup leading to ignition, toxic smoke, re-ignition or container failure.
Response guidance: Isolate, keep away from combustibles and moisture, monitor for heating, and use dry media unless SDS approves another method.
Firefighter training notes: Use this page as initial reference only; responders should train from ERG, SDS, department SOPs and product-specific preplans.
Regulatory context: UN 3185 is regulated for transport under its proper shipping name, hazard class 4 and ERG Guide 136. Verify current DOT/PHMSA requirements and shipping papers.
Storage & handling: Store only as permitted by the SDS and applicable code: segregate from incompatible materials, protect packages from heat, damage and moisture, and maintain labels.
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UN 3185 Quick Details
UN 3185
Product name: Self-heating liquid, corrosive, organic, n.o.s.
DOT Class: 4
Placard type: Spontaneously Combustible
ERG Guide: 136 (check current ERG)
Initial isolation: ERG 136: isolate spill area at least 25m in all directions; evacuate immediate area; if fire involves tank/rail car, isolate 800m and consider evacuation for 1600m in all directions
Common Hazards of UN 3185
- Self-heating liquid; may generate heat and ignite when exposed to air, moisture or contamination.
- Fire can develop without an outside ignition source if heat is not dissipated.
- Burning material may produce dense irritating, toxic or corrosive smoke.
- Water compatibility varies; water may worsen reaction or spread hot material.
- Containers may rupture when heated.
- Re-ignition is possible after apparent extinguishment.
- Because this is an n.o.s. entry, exact SDS data controls final tactics.
Chemical Identity & Physical Properties
Variable appearance depending on specific substance; typically a liquid at ambient or elevated temperature that may spontaneously heat when exposed to air. Often corrosive with irritating properties.
| Also known as | Self-heating corrosive liquidSpontaneously heating liquid corrosive organicPyrophoric corrosive liquid organic |
| Appearance | Variable appearance depending on specific substance; typically a liquid at ambient or elevated temperature that may spontaneously heat when exposed to air. Often corrosive with irritating properties. |
| Flash Point | Not applicable (self-heating/pyrophoric material) |
| Boiling Point | Variable depending on specific chemical composition |
| Vapor Density | Variable, typically heavier than air |
| Water Reactivity | Variable; avoid water or moisture until exact material compatibility is confirmed |
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Fireground Response Guidance — UN 3185
Extinguishing Media
Dry chemical, dry sand, soda ash or other SDS-approved dry media; avoid water unless confirmed compatible
PPE Requirements
⚠️ Level A or B required; full face SCBA mandatory; chemical-resistant suit due to corrosive nature; avoid skin contact
Use SCBA and chemical protective clothing; upgrade protection for toxic, corrosive or unknown vapor conditions.
Isolation & Evacuation
ERG 136: isolate spill area at least 25m in all directions; evacuate immediate area; if fire involves tank/rail car, isolate 800m and consider evacuation for 1600m in all directions
Always confirm protective actions with the current edition of the Emergency Response Guidebook (ERG Guide 136).
First Actions for a UN 3185 Incident
- Call 911 and the emergency response number shown on shipping papers.
- Keep unauthorized personnel away and establish an isolation perimeter.
- Stay upwind, uphill and upstream; avoid low areas where vapors or gases may collect.
- Avoid breathing vapors, dust, smoke or decomposition products.
- Do not touch damaged containers or spilled material without appropriate PPE.
- Separate from combustibles, moisture and ignition sources while monitoring for heat buildup.
- Ventilate confined spaces only if trained, equipped and atmospheric monitoring supports entry.
- Use ERG guidance, SDS, labels and shipping papers to confirm the exact hazards before action.
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📋 Copy & Share Field Card
UN 3185 — Self-heating liquid, corrosive, organic,HAZMAT RADIO NOTE — UN 3185
Product: Self-heating liquid, corrosive, organic, n.o.s.
Class 4 / Spontaneously Combustible / ERG 136
PPE: Level A or B required; full face SCBA mandatory; chemical-resistant suit due to corrosive nature; avoid skin contact
ISOLATION: ERG 136: isolate spill area at least 25m in all directions; evacuate immediate area; if fire involves tank/rail car, isolate 800m and consider evacuation for 1600m 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.
=== IC HAZMAT BRIEFING ===
UN 3185 — Self-heating liquid, corrosive, organic, n.o.s.
Class: 4 | Placard: Spontaneously Combustible | ERG Guide: 136
Appearance: Variable appearance depending on specific substance; typically a liquid at ambient or elevated temperature that may spontaneously heat when exposed to air. Often corrosive with irritating properties.
Water Reactivity: Variable; avoid water or moisture until exact material compatibility is confirmed
Extinguishing: Dry chemical, dry sand, soda ash or other SDS-approved dry media; avoid water unless confirmed compatible
PPE: Level A or B required; full face SCBA mandatory; chemical-resistant suit due to corrosive nature; avoid skin contact
Isolation: ERG 136: isolate spill area at least 25m in all directions; evacuate immediate area; if fire involves tank/rail car, isolate 800m and consider evacuation for 1600m in all directions
— Key Hazards —
• Self-heating liquid; may generate heat and ignite when exposed to air, moisture or contamination.
• Fire can develop without an outside ignition source if heat is not dissipated.
• Burning material may produce dense irritating, toxic or corrosive smoke.
— First Actions —
• Call 911 and the emergency response number shown on shipping papers.
• Keep unauthorized personnel away and establish an isolation perimeter.
• Stay upwind, uphill and upstream; avoid low areas where vapors or gases may collect.
• Avoid breathing vapors, dust, smoke or decomposition products.
SOURCE: allfirefighter.com/hazmat/un/self-heating-liquid-corrosive-un-3185 | Always use current ERG + SOP/SOGIC BRIEFING
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief.
UN3185 Self-heating liquid, corrosive, organic, n.o.s. Cls4 ERG136 | allfirefighter.com/hazmat/un/self-heating-liquid-corrosive-un-3185SMS / 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/self-heating-liquid-corrosive-un-3185
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Frequently Asked Questions about UN 3185
It is a broad corrosive, organic self-heating liquid entry; the exact product must be confirmed.
Yes. Self-heating materials can reach ignition temperature without an external flame.
Do not use water unless the SDS confirms compatibility; dry agents are safer for unknown products.
Use SCBA with chemical protective clothing; Level A may be needed for toxic or corrosive vapors.
Heat can remain inside the material and flare again when exposed to air.
Liquid or smoke may cause burns, so skin and eye protection are critical.
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.