☣️ UN 2012 • CLASS 4

Potassium phosphide

Placard: Dangerous When Wet. 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
Quick details
UN 2012
Class: 4
Placard type: Dangerous When Wet
ERG: Guide 139 (check current ERG)
Isolation: ERG 139: isolate spill 100m all directions; if fire isolate 800m and evacuate 1600m downwind
Chemical & Response Details
Also known asPhosphorus potassiumTripotassium phosphideK3P
CAS Number20770-41-6
AppearanceDark gray to black solid with no characteristic odor. Hygroscopic powder or crystalline material.
Flash PointNot applicable (water-reactive solid)
Boiling PointNot applicable (decomposes before boiling)
Vapor DensityNot applicable (solid)
Water ReactivityReacts violently with water producing flammable phosphine gas (PH3) and toxic fumes; do not use water
ExtinguishingDry sand, soda ash, dry chemical; absolutely no water or foam
PPE⚠️ Level A required; SCBA mandatory; full chemical protective suit due to toxic phosphine gas evolution
IsolationERG 139: isolate spill 100m all directions; if fire isolate 800m and evacuate 1600m downwind
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Common hazards (high level)
  • Produce flammable and toxic gases on contact with water.
  • May ignite on contact with water or moist air.
  • Some react vigorously or explosively on contact with water.
  • May be ignited by heat, sparks or flames.
  • May re-ignite after fire is extinguished.
  • Some are transported in highly flammable liquids.
  • Containers may explode when heated.
  • Runoff may create fire or explosion hazard.
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
Advertisement
📋 Copy & Share
UN 2012 — Potassium phosphide
HAZMAT RADIO NOTE — UN 2012 Product: Potassium phosphide Class 4 / Dangerous When Wet / ERG 139 PPE: Level A required; SCBA mandatory; full chemical protective suit due to toxic phosphine gas evolution ISOLATION: ERG 139: isolate spill 100m all directions; if fire isolate 800m and evacuate 1600m 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 2012 — Potassium phosphide Class: 4 | Placard: Dangerous When Wet | ERG Guide: 139 Appearance: Dark gray to black solid with no characteristic odor. Hygroscopic powder or crystalline material. Water Reactivity: Reacts violently with water producing flammable phosphine gas (PH3) and toxic fumes; do not use water Extinguishing: Dry sand, soda ash, dry chemical; absolutely no water or foam PPE: Level A required; SCBA mandatory; full chemical protective suit due to toxic phosphine gas evolution Isolation: ERG 139: isolate spill 100m all directions; if fire isolate 800m and evacuate 1600m downwind — Key Hazards — • Produce flammable and toxic gases on contact with water. • May ignite on contact with water or moist air. • Some react vigorously or explosively on contact with water. — 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/2012 | 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)
UN2012 Potassium phosphide Cls4 ERG139 | ERG 139: isolate spill 100m all directions; if fire isolate 800m and evacuate 16 | allfirefighter.com/hazmat/un/2012SMS / 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/2012
Related UN numbers (same class)
Discovery block for training / quick reference. Always consult the current ERG + your SOP/SOG for operations.
Advertisement

FAQ

Produce flammable and toxic gases on contact with water. May ignite on contact with water or moist air. Some react vigorously or explosively on contact with water. May be ignited by heat, sparks or flames. May re-ignite after fire is extinguished. Some are transported in highly flammable liquids. Containers may explode when heated. Runoff may create fire or explosion hazard.

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 required; SCBA mandatory; full chemical protective suit due to toxic phosphine gas evolution

No. This is a training/quick-reference aid only. Always consult the current ERG Guide 139 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.