☣️ UN 0492 • CLASS 1
UN 0492 — Signals, railway track, explosive
Placard: Explosive 1.3G. ERG Guide 112. 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 0492 Quick Details
UN 0492
Product name: Signals, railway track, explosive
DOT Class: 1
Placard type: Explosive 1.3G
ERG Guide: 112 (check current ERG)
Initial isolation: ERG 112: isolate 500m in all directions; if fire or explosion involved, evacuate 1600m radius; avoid direct contact or shock
Common Hazards of UN 0492
- Fire and burning hazard — not mass explosion.
- Intense heat and possible fragment projection.
- May deflagrate and initiate other materials.
- Smoke and toxic combustion products.
Chemical Identity & Physical Properties
| Also known as | Railway track signalsRailroad track torpedoesTrack warning devicesDetonating railway signalsTrack detonators |
| Appearance | Small explosive devices, typically metal or plastic casings containing primary explosives, designed to be placed on railroad tracks to produce audible warning signals. |
| Flash Point | Not applicable (explosive article) |
| Boiling Point | Not applicable (explosive article) |
| Vapor Density | Not applicable (solid explosive device) |
| Water Reactivity | No significant reaction with water under normal conditions |
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Fireground Response Guidance — UN 0492
Extinguishing Media
Do not use foam or water on burning explosives; use dry chemical or sand from safe distance
PPE Requirements
⚠️ Level B minimum with full face SCBA; blast-resistant gear recommended; maintain safe distance due to fragment projection risk
Isolation & Evacuation
ERG 112: isolate 500m in all directions; if fire or explosion involved, evacuate 1600m radius; avoid direct contact or shock
Always confirm protective actions with the current edition of the Emergency Response Guidebook (ERG Guide 112).
First Actions for a UN 0492 Incident
- CALL 911. Then call emergency response telephone number on shipping paper.
- Isolate area; stage upwind — fire and fragment hazard.
- Request Hazmat + law enforcement.
- Control ignition sources; deny entry.
- Consult current ERG Guide 112 and follow SOP/SOG.
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📋 Copy & Share Field Card
UN 0492 — Signals, railway track, explosiveHAZMAT RADIO NOTE — UN 0492
Product: Signals, railway track, explosive
Class 1 / Explosive 1.3G / ERG 112
PPE: Level B minimum with full face SCBA; blast-resistant gear recommended; maintain safe distance due to fragment projection risk
ISOLATION: ERG 112: isolate 500m in all directions; if fire or explosion involved, evacuate 1600m radius; avoid direct contact or shock
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 0492 — Signals, railway track, explosive
Class: 1 | Placard: Explosive 1.3G | ERG Guide: 112
Appearance: Small explosive devices, typically metal or plastic casings containing primary explosives, designed to be placed on railroad tracks to produce audible warning signals.
Water Reactivity: No significant reaction with water under normal conditions
Extinguishing: Do not use foam or water on burning explosives; use dry chemical or sand from safe distance
PPE: Level B minimum with full face SCBA; blast-resistant gear recommended; maintain safe distance due to fragment projection risk
Isolation: ERG 112: isolate 500m in all directions; if fire or explosion involved, evacuate 1600m radius; avoid direct contact or shock
— Key Hazards —
• Fire and burning hazard — not mass explosion.
• Intense heat and possible fragment projection.
• May deflagrate and initiate other materials.
— First Actions —
• CALL 911. Then call emergency response telephone number on shipping paper.
• Isolate area; stage upwind — fire and fragment hazard.
• Request Hazmat + law enforcement.
• Control ignition sources; deny entry.
SOURCE: allfirefighter.com/hazmat/un/0492 | Always use current ERG + SOP/SOGIC BRIEFING
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief. Full chemical + response details.
UN0492 Signals, railway track, explosive Cls1 ERG112 | allfirefighter.com/hazmat/un/0492SMS / 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/0492
Related UN Numbers in Class 1
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 0492
Fire and burning hazard — not mass explosion. Intense heat and possible fragment projection. May deflagrate and initiate other materials. Smoke and toxic combustion products.
CALL 911. Then call emergency response telephone number on shipping paper. Isolate area; stage upwind — fire and fragment hazard. Request Hazmat + law enforcement.
Level B minimum with full face SCBA; blast-resistant gear recommended; maintain safe distance due to fragment projection risk
Water reactivity: No significant reaction with water under normal conditions. Recommended extinguishing: Do not use foam or water on burning explosives; use dry chemical or sand from safe distance.
ERG Guide 112 recommendation: ERG 112: isolate 500m in all directions; if fire or explosion involved, evacuate 1600m radius; avoid direct contact or shock
No. This is a training/quick-reference aid only. Always consult the current ERG Guide 112 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.