☣️ UN 3370 • CLASS 4
UN 3370 — Urea nitrate, wetted with not less than 10% water
Placard: Flammable Solid. ERG Guide 113. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
🚒☣️
⚠️ 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.
UN 3370 is Urea nitrate, wetted with not less than 10% water, assigned to ERG Guide 113. First responders should verify the shipping papers and SDS, isolate the area, and base entry, PPE and control tactics on the product's listed hazards.
Hazard overview: The main hazard is a wetted energetic solid that may burn and can become explosive if dried out, heated, shocked, or contaminated.
Response guidance: For UN 3370, isolate the area, avoid shock and friction, prevent drying, cool exposed containers from distance, and treat dried or burning material as an explosive hazard.
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UN 3370 Quick Details
UN 3370
Product name: Urea nitrate, wetted with not less than 10% water
DOT Class: 4
Placard type: Flammable Solid
ERG Guide: 113 (check current ERG)
Initial isolation: ERG 113: Isolate spill 25m (80ft) all directions. For fire: isolate 800m (0.5 miles) initially in all directions, evacuate if tank/rail car involved.
Common Hazards of UN 3370
- Flammable/combustible material.
- May be ignited by heat, sparks or flames.
- DRIED OUT material may explode if exposed to heat, flame, friction or shock; treat as an explosive hazard.
- Keep material wet with water or treat as an explosive (GUIDE 112).
- Runoff to sewer may create fire or explosion hazard.
- Some are toxic and may be fatal if inhaled, ingested or absorbed through skin.
- Contact may cause burns to skin and eyes.
- Fire may produce irritating, corrosive and/or toxic gases.
Chemical Identity & Physical Properties
White to pale yellow crystalline solid or powder. Odorless or slight ammonia-like odor. Shipped as a wetted paste or slurry to reduce explosion hazard.
| Also known as | Urea mononitrateCarbamide nitrateNitratoureaAcidulated urea |
| CAS Number | 124-47-0 |
| Appearance | White to pale yellow crystalline solid or powder. Odorless or slight ammonia-like odor. Shipped as a wetted paste or slurry to reduce explosion hazard. |
| Flash Point | Not applicable (oxidizing solid, not combustible itself but enhances combustion) |
| Boiling Point | Not applicable (decomposes before boiling at approximately 152C/306F) |
| Vapor Density | Not applicable (solid) |
| Water Reactivity | Soluble in water; no violent reaction. Water acts as desensitizer and prevents detonation. |
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Fireground Response Guidance — UN 3370
Extinguishing Media
Water spray to keep containers cool; CO2, dry chemical for small fires. Do NOT dry out material.
PPE Requirements
⚠️ Level B minimum with SCBA required. Full protective clothing and face shield. Avoid all contact with dried material.
Level B minimum with SCBA required. Full protective clothing and face shield. Avoid all contact with dried material.
Isolation & Evacuation
ERG 113: Isolate spill 25m (80ft) all directions. For fire: isolate 800m (0.5 miles) initially in all directions, evacuate if tank/rail car involved.
Always confirm protective actions with the current edition of the Emergency Response Guidebook (ERG Guide 113).
First Actions for a UN 3370 Incident
- CALL 911. Then call the emergency response telephone number on the shipping paper, if available.
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Ventilate closed spaces before entering, but only if properly trained and equipped.
- Isolate spill or leak area immediately for at least 100 meters (330 feet) in all directions.
- Consider initial evacuation for 500 meters (1/3 mile) in all directions.
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📋 Copy & Share Field Card
UN 3370 — Urea nitrate, wetted with not less thanHAZMAT RADIO NOTE — UN 3370
Product: Urea nitrate, wetted with not less than 10% water
Class 4 / Flammable Solid / ERG 113
PPE: Level B minimum with SCBA required. Full protective clothing and face shield. Avoid all contact with dried material.
ISOLATION: ERG 113: Isolate spill 25m (80ft) all directions. For fire: isolate 800m (0.5 miles) initially in all directions, evacuate if tank/rail car involved.
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 3370 — Urea nitrate, wetted with not less than 10% water
Class: 4 | Placard: Flammable Solid | ERG Guide: 113
Appearance: White to pale yellow crystalline solid or powder. Odorless or slight ammonia-like odor. Shipped as a wetted paste or slurry to reduce explosion hazard.
Water Reactivity: Soluble in water; no violent reaction. Water acts as desensitizer and prevents detonation.
Extinguishing: Water spray to keep containers cool; CO2, dry chemical for small fires. Do NOT dry out material.
PPE: Level B minimum with SCBA required. Full protective clothing and face shield. Avoid all contact with dried material.
Isolation: ERG 113: Isolate spill 25m (80ft) all directions. For fire: isolate 800m (0.5 miles) initially in all directions, evacuate if tank/rail car involved.
— Key Hazards —
• Flammable/combustible material.
• May be ignited by heat, sparks or flames.
• DRIED OUT material may explode if exposed to heat, flame, friction or shock; treat as an explosive hazard.
— First Actions —
• CALL 911. Then call the emergency response telephone number on the shipping paper, if available.
• Keep unauthorized personnel away.
• Stay upwind, uphill and/or upstream.
• Ventilate closed spaces before entering, but only if properly trained and equipped.
SOURCE: allfirefighter.com/hazmat/un/urea-nitrate-wetted-with-un-3370 | Always use current ERG + SOP/SOGIC BRIEFING
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief.
UN3370 Urea nitrate, wetted with not less than 10% water Cls4 ERG113 | allfirefighter.com/hazmat/un/urea-nitrate-wetted-with-un-3370SMS / 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/urea-nitrate-wetted-with-un-3370
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Frequently Asked Questions about UN 3370
UN 3370 is Urea nitrate, wetted with not less than 10% water. It is assigned to ERG Guide 113 for initial emergency response.
The wetting or desensitizing agent lowers explosion sensitivity. If the material dries out, it may become shock-, friction-, or heat-sensitive.
It is shipped desensitized or wetted, but dried or heated material should be treated as an explosive hazard.
Cool containers from a distance and prevent drying. Do not disturb dried material; request specialist explosive/hazmat support.
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.