☣️ UN 2745 • CLASS 6

Chloromethyl chloroformate

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 2745
Class: 6
Placard type: Toxic
ERG: Guide 157 (check current ERG)
Isolation: ERG 157: isolate spill/leak area immediately for at least 50m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and consider evacuation for 800m in all directions
Chemical & Response Details
Also known asChloromethyl chlorocarbonateChloroformic acid chloromethyl esterCarbonochloridic acid chloromethyl ester
CAS Number22128-62-7
AppearanceColorless to pale yellow liquid with a pungent, irritating odor. Fumes in moist air due to reaction with atmospheric moisture.
Flash PointNot readily available; presents primarily toxic/corrosive hazard
Boiling Point105-107C (221-225F)
Vapor Density~4.4 (heavier than air)
Water ReactivityReacts with water and moist air releasing toxic and corrosive hydrogen chloride (HCl) and formaldehyde gases; reaction generates heat
ExtinguishingCO2, dry chemical powder; avoid water-based agents due to water reactivity
PPE⚠️ Level A or B with full-face SCBA required; butyl rubber or Viton gloves and suit; severe inhalation and skin contact hazard
IsolationERG 157: isolate spill/leak area immediately for at least 50m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and consider evacuation for 800m in all directions
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 contact (skin, eyes) with vapors, dusts or substance
  • Reaction with water or moist air may release toxic, corrosive or flammable gases.
  • Reaction with water may generate much heat that will increase the concentration of fumes in the air.
  • Fire will 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
  • UN1802, UN2032, UN3084, UN3093, UN1796 (above 50%), UN1826 (above 50%), and UN2031 (above
  • Vapors may accumulate in confined areas (basement, tanks, hopper/tank cars, etc.).
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 2745 — Chloromethyl chloroformate
HAZMAT RADIO NOTE — UN 2745 Product: Chloromethyl chloroformate Class 6 / Toxic / ERG 157 PPE: Level A or B with full-face SCBA required; butyl rubber or Viton gloves and suit; severe inhalation and skin contact hazard ISOLATION: ERG 157: isolate spill/leak area immediately for at least 50m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and consider evacuation for 800m in all directions 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 2745 — Chloromethyl chloroformate Class: 6 | Placard: Toxic | ERG Guide: 157 Appearance: Colorless to pale yellow liquid with a pungent, irritating odor. Fumes in moist air due to reaction with atmospheric moisture. Water Reactivity: Reacts with water and moist air releasing toxic and corrosive hydrogen chloride (HCl) and formaldehyde gases; reaction generates heat Extinguishing: CO2, dry chemical powder; avoid water-based agents due to water reactivity PPE: Level A or B with full-face SCBA required; butyl rubber or Viton gloves and suit; severe inhalation and skin contact hazard Isolation: ERG 157: isolate spill/leak area immediately for at least 50m in all directions; if tank/rail car involved in fire, isolate 800m in all directions and consider evacuation for 800m in all directions — Key Hazards — • TOXIC and/or CORROSIVE; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance • Reaction with water or moist air may release toxic, corrosive or flammable gases. • Reaction with water may generate much heat that will increase the concentration of fumes in the air. — 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/2745 | 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)
UN2745 Chloromethyl chloroformate Cls6 ERG157 | allfirefighter.com/hazmat/un/2745SMS / 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/2745
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 contact (skin, eyes) with vapors, dusts or substance Reaction with water or moist air may release toxic, corrosive or flammable gases. Reaction with water may generate much heat that will increase the concentration of fumes in the air. Fire will 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 UN1802, UN2032, UN3084, UN3093, UN1796 (above 50%), UN1826 (above 50%), and UN2031 (above Vapors may accumulate in confined areas (basement, tanks, hopper/tank cars, etc.).

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 A or B with full-face SCBA required; butyl rubber or Viton gloves and suit; severe inhalation and skin contact hazard

No. This is a training/quick-reference aid only. Always consult the current ERG Guide 157 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.