☣️ UN 3428 • CLASS 6

3-Chloro-4-methylphenyl isocyanate, solid

Placard: Toxic. 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.
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Quick details
UN 3428
Class: 6
Placard type: Toxic
ERG: Guide 156 (check current ERG)
Isolation: ERG 156: Isolate spill area immediate 25m in all directions. For large spills isolate 50m and consider evacuation 300m downwind.
Chemical & Response Details
Also known as3-Chloro-4-methylphenyl isocyanateIsocyanic acid, 3-chloro-4-methylphenyl ester4-Methyl-3-chlorophenyl isocyanate3-Chloro-4-cresyl isocyanate
CAS Number28479-22-3
AppearanceWhite to light tan crystalline solid with a sharp, pungent odor. Combustible at elevated temperatures.
Flash Point113°C (235°F)
Boiling PointDecomposes before boiling
Vapor DensityNot applicable (solid at room temperature)
Water ReactivityReacts with water liberating toxic and corrosive gases including hydrogen chloride and carbon dioxide. Avoid water contact.
ExtinguishingDry chemical, CO2, dry sand. Do not use water or foam directly on material.
PPE⚠️ Level B minimum with SCBA required. Full chemical resistant suit for spill response. Avoid all skin and eye contact.
IsolationERG 156: Isolate spill area immediate 25m in all directions. For large spills isolate 50m and consider evacuation 300m downwind.
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Common hazards (high level)
  • Combustible material: may burn but does not ignite readily.
  • Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff.
  • When heated, vapors may form explosive mixtures with air: indoors, outdoors and sewers explosion
  • Most vapors are heavier than air. They will spread along the ground and collect in low or confined areas
  • Vapors may travel to source of ignition and flash back.
  • Corrosives in contact with metals may evolve flammable hydrogen gas.
  • Containers may explode when heated or if contaminated with water.
  • TOXIC and/or CORROSIVE; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance
First actions (field-minded)
  • CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper
  • 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 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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UN 3428 — 3-Chloro-4-methylphenyl isocyanate, soli
HAZMAT RADIO NOTE — UN 3428 Product: 3-Chloro-4-methylphenyl isocyanate, solid Class 6 / Toxic / ERG 156 PPE: Level B minimum with SCBA required. Full chemical resistant suit for spill response. Avoid all skin and eye contact. ISOLATION: ERG 156: Isolate spill area immediate 25m in all directions. For large spills isolate 50m and consider evacuation 300m downwind. ACTION: Stage upwind · Isolate · Deny entry · Request HazmatRADIO

Use for: Quick radio or face-to-face size-up. Short, structured, field-ready.

SMS WhatsApp
=== IC HAZMAT BRIEFING === UN 3428 — 3-Chloro-4-methylphenyl isocyanate, solid Class: 6 | Placard: Toxic | ERG Guide: 156 Appearance: White to light tan crystalline solid with a sharp, pungent odor. Combustible at elevated temperatures. Water Reactivity: Reacts with water liberating toxic and corrosive gases including hydrogen chloride and carbon dioxide. Avoid water contact. Extinguishing: Dry chemical, CO2, dry sand. Do not use water or foam directly on material. PPE: Level B minimum with SCBA required. Full chemical resistant suit for spill response. Avoid all skin and eye contact. Isolation: ERG 156: Isolate spill area immediate 25m in all directions. For large spills isolate 50m and consider evacuation 300m downwind. — Key Hazards — • Combustible material: may burn but does not ignite readily. • Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff. • When heated, vapors may form explosive mixtures with air: indoors, outdoors and sewers explosion — 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. • Ventilate closed spaces before entering, but only if properly trained and equipped. SOURCE: allfirefighter.com/hazmat/un/3428 | Always use current ERG + SOP/SOGIC BRIEFING

Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief. Full chemical + response details.

SMS (short)
UN3428 3-Chloro-4-methylphenyl isocyanate, solid Cls6 ERG156 | allfirefighter.com/hazmat/un/3428SMS / 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/3428
Related UN numbers (same class)
Discovery block for training / quick reference. Always consult the current ERG + your SOP/SOG for operations.
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FAQ

Combustible material: may burn but does not ignite readily. Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff. When heated, vapors may form explosive mixtures with air: indoors, outdoors and sewers explosion Most vapors are heavier than air. They will spread along the ground and collect in low or confined areas Vapors may travel to source of ignition and flash back. Corrosives in contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or if contaminated with water. TOXIC and/or CORROSIVE; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance

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 SCBA required. Full chemical resistant suit for spill response. Avoid all skin and eye contact.

No. This is a training/quick-reference aid only. Always consult the current ERG Guide 156 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.