☣️ UN 2778 • CLASS 3
Mercury based pesticide, liquid, flammable, poisonous
Placard: Flammable. 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 2778
Class: 3
Placard type: Flammable
ERG: Guide 131 (check current ERG)
Isolation: ERG 131: Initial isolate 50m all directions; protect persons downwind; large spill isolate 300m; if fire/tank involved evacuate 800m radius
Chemical & Response Details
| Also known as | Mercury pesticide liquidMercurial pesticide solutionOrganomercury pesticide formulationAlkylmercury pesticide |
| Appearance | Clear to colored liquid with characteristic pesticide odor. May range from colorless to amber or brown depending on formulation. Flammable toxic liquid at room temperature. |
| Flash Point | 23-61C (73-142F) typical for Class 3 flammable liquid |
| Boiling Point | Varies by formulation, typically 65-150C (149-302F) |
| Vapor Density | Greater than 1 (heavier than air) |
| Water Reactivity | No significant violent reaction, but may be slightly water-reactive or hydrolyze slowly releasing toxic mercury compounds |
| Extinguishing | Alcohol-resistant foam, CO2, dry chemical; water spray for cooling only |
| PPE | ⚠️ Level A or B required; full SCBA mandatory; chemical-resistant suit; mercury vapor highly toxic; avoid all skin contact |
| Isolation | ERG 131: Initial isolate 50m all directions; protect persons downwind; large spill isolate 300m; if fire/tank involved evacuate 800m radius |
Chemical details are general reference only. Always verify with current SDS, ERG, and SOP/SOG.
Common hazards (high level)
- TOXIC; may be fatal if inhaled, ingested or absorbed through skin.
- Inhalation or contact with some of these materials will irritate or burn skin and eyes.
- Methyl chloroacetate (UN2295) is an eye irritant/lachrymator (causes flow of tears).
- Fire will produce irritating, corrosive and/or toxic gases.
- Vapors may cause dizziness or asphyxiation, especially when in closed or confined areas.
- Runoff from fire control or dilution water may cause environmental contamination.
- HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.
- Vapors may form explosive mixtures with air.
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 for at least 50 meters (150 feet) in all directions.
- 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 2778 — Mercury based pesticide, liquid, flammab HAZMAT RADIO NOTE — UN 2778
Product: Mercury based pesticide, liquid, flammable, poisonous
Class 3 / Flammable / ERG 131
PPE: Level A or B required; full SCBA mandatory; chemical-resistant suit; mercury vapor highly toxic; avoid all skin contact
ISOLATION: ERG 131: Initial isolate 50m all directions; protect persons downwind; large spill isolate 300m; if fire/tank involved evacuate 800m radius
ACTION: Stage upwind · Isolate · Deny entry · Request HazmatRADIO
Use for: Quick radio or face-to-face size-up. Short, structured, field-ready.
=== IC HAZMAT BRIEFING ===
UN 2778 — Mercury based pesticide, liquid, flammable, poisonous
Class: 3 | Placard: Flammable | ERG Guide: 131
Appearance: Clear to colored liquid with characteristic pesticide odor. May range from colorless to amber or brown depending on formulation. Flammable toxic liquid at room temperature.
Water Reactivity: No significant violent reaction, but may be slightly water-reactive or hydrolyze slowly releasing toxic mercury compounds
Extinguishing: Alcohol-resistant foam, CO2, dry chemical; water spray for cooling only
PPE: Level A or B required; full SCBA mandatory; chemical-resistant suit; mercury vapor highly toxic; avoid all skin contact
Isolation: ERG 131: Initial isolate 50m all directions; protect persons downwind; large spill isolate 300m; if fire/tank involved evacuate 800m radius
— Key Hazards —
• TOXIC; may be fatal if inhaled, ingested or absorbed through skin.
• Inhalation or contact with some of these materials will irritate or burn skin and eyes.
• Methyl chloroacetate (UN2295) is an eye irritant/lachrymator (causes flow of tears).
— 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/2778 | Always use current ERG + SOP/SOGIC BRIEFING
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief. Full chemical + response details.
UN2778 Mercury based pesticide, liquid, flammable, poisonous Cls3 ERG131 | allfirefighter.com/hazmat/un/2778SMS / 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/2778
Advertisement
FAQ
TOXIC; may be fatal if inhaled, ingested or absorbed through skin. Inhalation or contact with some of these materials will irritate or burn skin and eyes. Methyl chloroacetate (UN2295) is an eye irritant/lachrymator (causes flow of tears). Fire will produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or asphyxiation, especially when in closed or confined areas. Runoff from fire control or dilution water may cause environmental contamination. HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air.
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 required; full SCBA mandatory; chemical-resistant suit; mercury vapor highly toxic; avoid all skin contact
No. This is a training/quick-reference aid only. Always consult the current ERG Guide 131 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.