☣️ UN 2496 • CLASS 8

Propionic anhydride

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 2496
Class: 8
Placard type: Corrosive
ERG: Guide 156 (check current ERG)
Isolation: ERG 156: isolate 50m all directions; for large spill consider initial evacuation 300m downwind
Chemical & Response Details
Also known asPropanoic anhydrideMethylacetic anhydridePropanoic acid anhydridePropionic acid anhydride
CAS Number123-62-6
AppearanceColorless to pale yellow liquid with a pungent, acrid odor. Fuming liquid at room temperature.
Flash Point63°C (145°F)
Boiling Point167°C (333°F)
Vapor Density4.4 (heavier than air)
Water ReactivityReacts with water liberating heat and propionic acid; violent reaction possible with large quantities
ExtinguishingAlcohol-resistant foam, dry chemical, CO2; water spray for cooling only
PPE⚠️ Level B minimum; SCBA and chemical-resistant suit required; avoid all skin/eye contact
IsolationERG 156: isolate 50m all directions; for large spill consider initial 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 2496 — Propionic anhydride
HAZMAT RADIO NOTE — UN 2496 Product: Propionic anhydride Class 8 / Corrosive / ERG 156 PPE: Level B minimum; SCBA and chemical-resistant suit required; avoid all skin/eye contact ISOLATION: ERG 156: isolate 50m all directions; for large spill consider initial 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 2496 — Propionic anhydride Class: 8 | Placard: Corrosive | ERG Guide: 156 Appearance: Colorless to pale yellow liquid with a pungent, acrid odor. Fuming liquid at room temperature. Water Reactivity: Reacts with water liberating heat and propionic acid; violent reaction possible with large quantities Extinguishing: Alcohol-resistant foam, dry chemical, CO2; water spray for cooling only PPE: Level B minimum; SCBA and chemical-resistant suit required; avoid all skin/eye contact Isolation: ERG 156: isolate 50m all directions; for large spill consider initial 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/2496 | 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)
UN2496 Propionic anhydride Cls8 ERG156 | ERG 156: isolate 50m all directions; for large spill consider initial evacuation | allfirefighter.com/hazmat/un/2496SMS / 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/2496
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; SCBA and chemical-resistant suit required; avoid all skin/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.