☣️ UN 3261 • CLASS 8

Corrosive solid, acidic, organic, n.o.s.

Placard: Corrosive. 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 3261
Class: 8
Placard type: Corrosive
ERG: Guide 154 (check current ERG)
Isolation: ERG 154: Initial isolation 25m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and consider evacuation
Chemical & Response Details
Also known asCorrosive solid, acidic, organic, not otherwise specifiedAcidic organic corrosive solidOrganic acid solidCorrosive organic solid, acidic
AppearanceSolid material at room temperature, varying in color and form depending on specific substance. May be crystalline, granular, or powdered; specific physical properties vary by composition as this is a general classification for various organic acidic solids.
Flash PointNot applicable (solid, varies by specific substance)
Boiling PointNot applicable (varies by specific substance)
Vapor DensityNot applicable (solid)
Water ReactivityMay react with water generating heat; reaction severity depends on specific substance; handle with caution around water
ExtinguishingDry chemical, CO2, or dry sand preferred; avoid direct water streams; fog spray acceptable for cooling
PPE⚠️ Level B minimum required; full face SCBA mandatory; chemical-resistant suit and gloves essential; avoid any skin contact due to severe corrosive nature
IsolationERG 154: Initial isolation 25m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and consider evacuation
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Common hazards (high level)
  • 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.
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 3261 — Corrosive solid, acidic, organic, n.o.s.
HAZMAT RADIO NOTE — UN 3261 Product: Corrosive solid, acidic, organic, n.o.s. Class 8 / Corrosive / ERG 154 PPE: Level B minimum required; full face SCBA mandatory; chemical-resistant suit and gloves essential; avoid any skin contact due to severe corrosive nature ISOLATION: ERG 154: Initial isolation 25m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and consider evacuation 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 3261 — Corrosive solid, acidic, organic, n.o.s. Class: 8 | Placard: Corrosive | ERG Guide: 154 Appearance: Solid material at room temperature, varying in color and form depending on specific substance. May be crystalline, granular, or powdered; specific physical properties vary by composition as this is a general classification for various organic acidic solids. Water Reactivity: May react with water generating heat; reaction severity depends on specific substance; handle with caution around water Extinguishing: Dry chemical, CO2, or dry sand preferred; avoid direct water streams; fog spray acceptable for cooling PPE: Level B minimum required; full face SCBA mandatory; chemical-resistant suit and gloves essential; avoid any skin contact due to severe corrosive nature Isolation: ERG 154: Initial isolation 25m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and consider evacuation — 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/3261 | 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)
UN3261 Corrosive solid, acidic, organic, n.o.s. Cls8 ERG154 | allfirefighter.com/hazmat/un/3261SMS / 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/3261
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

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 required; full face SCBA mandatory; chemical-resistant suit and gloves essential; avoid any skin contact due to severe corrosive nature

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.