☣️ UN 2331 • CLASS 8

UN 2331 — Zinc chloride, anhydrous

Placard: Corrosive. ERG Guide 154. 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.
Advertisement

UN 2331 Quick Details

UN 2331
Product name: Zinc chloride, anhydrous
DOT Class: 8
Placard type: Corrosive
ERG Guide: 154 (check current ERG)
Initial isolation: ERG 154: Small spill isolate 25m all directions; Large spill isolate 50m, downwind 300m initial

Common Hazards of UN 2331

  • TOXIC and/or CORROSIVE; inhalation, ingestion or skin contact with material may cause severe injury
  • Contact with molten substance may cause severe burns to skin and eyes.
  • Avoid any skin contact.
  • Fire may produce irritating, corrosive and/or toxic gases.
  • Runoff from fire control or dilution water may be corrosive and/or toxic and cause environmental
  • Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive
  • Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.).
  • Corrosives in contact with metals may evolve flammable hydrogen gas.

Chemical Identity & Physical Properties

Also known asButter of zincZinc dichlorideZinc(II) chlorideZnCl2
CAS Number7646-85-7
AppearanceWhite to grayish-white crystalline solid or granular powder. Odorless to slight odor. Highly hygroscopic, absorbs moisture from air.
Flash PointNot applicable (non-flammable solid)
Boiling Point732C (1350F)
Vapor DensityNot applicable (solid)
Water ReactivityDissolves in water with heat generation; highly exothermic reaction, may cause solution to boil
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.

Fireground Response Guidance — UN 2331

Extinguishing Media

Water spray, dry chemical, CO2; avoid direct water streams on hot material

PPE Requirements

⚠️ Level B minimum; full face protection, chemical-resistant suit, gloves; SCBA for fire or confined spaces

Isolation & Evacuation

ERG 154: Small spill isolate 25m all directions; Large spill isolate 50m, downwind 300m initial
Always confirm protective actions with the current edition of the Emergency Response Guidebook (ERG Guide 154).

First Actions for a UN 2331 Incident

  • 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
Advertisement

📋 Copy & Share Field Card

UN 2331 — Zinc chloride, anhydrous
HAZMAT RADIO NOTE — UN 2331 Product: Zinc chloride, anhydrous Class 8 / Corrosive / ERG 154 PPE: Level B minimum; full face protection, chemical-resistant suit, gloves; SCBA for fire or confined spaces ISOLATION: ERG 154: Small spill isolate 25m all directions; Large spill isolate 50m, downwind 300m initial 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 2331 — Zinc chloride, anhydrous Class: 8 | Placard: Corrosive | ERG Guide: 154 Appearance: White to grayish-white crystalline solid or granular powder. Odorless to slight odor. Highly hygroscopic, absorbs moisture from air. Water Reactivity: Dissolves in water with heat generation; highly exothermic reaction, may cause solution to boil Extinguishing: Water spray, dry chemical, CO2; avoid direct water streams on hot material PPE: Level B minimum; full face protection, chemical-resistant suit, gloves; SCBA for fire or confined spaces Isolation: ERG 154: Small spill isolate 25m all directions; Large spill isolate 50m, downwind 300m initial — Key Hazards — • TOXIC and/or CORROSIVE; inhalation, ingestion or skin contact with material may cause severe injury • Contact with molten substance may cause severe burns to skin and eyes. • Avoid any skin contact. — 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/2331 | 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)
UN2331 Zinc chloride, anhydrous Cls8 ERG154 | allfirefighter.com/hazmat/un/2331SMS / 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/2331

Related UN Numbers in Class 8

Discovery block for training / quick reference. Always consult the current ERG + your SOP/SOG for operations.
Advertisement

Frequently Asked Questions about UN 2331

TOXIC and/or CORROSIVE; inhalation, ingestion or skin contact with material may cause severe injury Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause environmental Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Corrosives in contact with metals may evolve flammable hydrogen gas.

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; full face protection, chemical-resistant suit, gloves; SCBA for fire or confined spaces

Water reactivity: Dissolves in water with heat generation; highly exothermic reaction, may cause solution to boil. Recommended extinguishing: Water spray, dry chemical, CO2; avoid direct water streams on hot material.

ERG Guide 154 recommendation: ERG 154: Small spill isolate 25m all directions; Large spill isolate 50m, downwind 300m initial

No. This is a training/quick-reference aid only. Always consult the current ERG Guide 154 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.