☣️ UN 1326 • CLASS 4

Hafnium powder, wetted with not less than 25% water

Placard: Flammable Solid. 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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Quick details
UN 1326
Class: 4
Placard type: Flammable Solid
ERG: Guide 170 (check current ERG)
Isolation: ERG 170: isolate spill 25m all directions. If fire, isolate 800m and consider evacuation 800m downwind.
Chemical & Response Details
Also known asHafnium metal powderHafnium powder wettedHf powderHafnium flammable solid
CAS Number7440-58-6
AppearanceGray to silver metallic powder, odorless. Shipped wetted with minimum 25% water to reduce pyrophoric hazard.
Flash PointNot applicable (pyrophoric metal powder when dry)
Boiling Point4603C (8317F)
Vapor DensityNot applicable (solid metal)
Water ReactivityReacts with water when dry, generating heat and hydrogen gas. Wetted form designed to prevent ignition.
ExtinguishingDry sand, dry chemical, soda ash. Do not use water or foam on dry material.
PPE⚠️ Level B minimum; full face respirator, chemical-resistant gloves and suit. SCBA if fire involved.
IsolationERG 170: isolate spill 25m all directions. If fire, isolate 800m and consider evacuation 800m downwind.
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Common hazards (high level)
  • May react violently or explosively on contact with water.
  • Some are transported in flammable liquids.
  • May be ignited by friction, heat, sparks or flames.
  • Some of these materials will burn with intense heat.
  • Dusts or fumes may form explosive mixtures in air.
  • Containers may explode when heated.
  • May re-ignite after fire is extinguished.
  • Oxides from metallic fires are a severe health hazard.
First actions (field-minded)
  • CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper
  • Stay upwind, uphill and/or upstream.
  • Keep unauthorized personnel away.
  • Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters
  • Consider initial downwind evacuation for at least 50 meters (160 feet).
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UN 1326 — Hafnium powder, wetted with not less tha
HAZMAT RADIO NOTE — UN 1326 Product: Hafnium powder, wetted with not less than 25% water Class 4 / Flammable Solid / ERG 170 PPE: Level B minimum; full face respirator, chemical-resistant gloves and suit. SCBA if fire involved. ISOLATION: ERG 170: isolate spill 25m all directions. If fire, isolate 800m and consider evacuation 800m 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 1326 — Hafnium powder, wetted with not less than 25% water Class: 4 | Placard: Flammable Solid | ERG Guide: 170 Appearance: Gray to silver metallic powder, odorless. Shipped wetted with minimum 25% water to reduce pyrophoric hazard. Water Reactivity: Reacts with water when dry, generating heat and hydrogen gas. Wetted form designed to prevent ignition. Extinguishing: Dry sand, dry chemical, soda ash. Do not use water or foam on dry material. PPE: Level B minimum; full face respirator, chemical-resistant gloves and suit. SCBA if fire involved. Isolation: ERG 170: isolate spill 25m all directions. If fire, isolate 800m and consider evacuation 800m downwind. — Key Hazards — • May react violently or explosively on contact with water. • Some are transported in flammable liquids. • May be ignited by friction, heat, sparks or flames. — First Actions — • CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper • Stay upwind, uphill and/or upstream. • Keep unauthorized personnel away. • Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters SOURCE: allfirefighter.com/hazmat/un/1326 | 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)
UN1326 Hafnium powder, wetted with not less than 25% water Cls4 ERG170 | allfirefighter.com/hazmat/un/1326SMS / 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/1326
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

May react violently or explosively on contact with water. Some are transported in flammable liquids. May be ignited by friction, heat, sparks or flames. Some of these materials will burn with intense heat. Dusts or fumes may form explosive mixtures in air. Containers may explode when heated. May re-ignite after fire is extinguished. Oxides from metallic fires are a severe health hazard.

CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper Stay upwind, uphill and/or upstream. Keep unauthorized personnel away.

Level B minimum; full face respirator, chemical-resistant gloves and suit. SCBA if fire involved.

No. This is a training/quick-reference aid only. Always consult the current ERG Guide 170 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.