UN 2781 — Bipyridilium pesticide, solid, poisonous
Placard: Toxic. ERG Guide 151. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
Bipyridilium pesticide, solid, poisonous is a variable toxic pesticide solid. Appearance, active ingredient and concentration can differ, so SDS and shipping papers drive final response decisions.
Hazard overview: Bipyridilium pesticide may be highly toxic by inhalation, ingestion or skin absorption. Liquid or dust contact can irritate or burn skin and eyes depending on the formulation. Fire or heating may produce irritating, toxic and corrosive decomposition products.
Response guidance: For a Bipyridilium pesticide, solid, poisonous release, isolate the area, remove ignition sources if present, and keep runoff out of drains. Responders should use SCBA with chemical-resistant clothing and base tactics on SDS, shipping papers and monitoring.
Firefighter training notes: Train responders to identify the UN number, product name, placard, container type and exposure route before committing personnel to the hot zone.
Regulatory context: Use the proper DOT shipping description, ERG guide, SDS and site-specific response plan; do not substitute this summary for regulatory compliance.
Storage & handling: Store in sealed containers away from food/feed, incompatible chemicals, drains, heat and moisture; prevent dust release.
UN 2781 Quick Details
Common Hazards of UN 2781
- Bipyridilium pesticide may be highly toxic by inhalation, ingestion or skin absorption.
- Liquid or dust contact can irritate or burn skin and eyes depending on the formulation.
- Fire or heating may produce irritating, toxic and corrosive decomposition products.
- Runoff, wash water and contaminated absorbent can carry pesticide into drains or waterways.
- Exact active ingredient, solvent carrier and concentration must be verified from SDS and shipping papers.
- The product may not burn readily, but packaging or contaminated material can burn in a fire.
- Dust or residues should not be dispersed during cleanup.
- Containers may rupture when heated.
Chemical Identity & Physical Properties
Typically appears as white to tan or yellowish crystalline solid or granular powder. Odorless or slight characteristic odor. Solid at room temperature.
| Also known as | DiquatParaquatBipyridinium herbicideDipyridyl pesticideQuaternary ammonium herbicide |
| Appearance | Typically appears as white to tan or yellowish crystalline solid or granular powder. Odorless or slight characteristic odor. Solid at room temperature. |
| Flash Point | Not applicable (non-flammable solid) |
| Boiling Point | Not applicable (decomposes before boiling) |
| Vapor Density | Not applicable (solid) |
| Water Reactivity | No violent water reaction is expected, but wetting can create toxic runoff or slurry; keep material out of drains. |
Fireground Response Guidance — UN 2781
Extinguishing Media
PPE Requirements
Level A or B required; full chemical protective suit, SCBA mandatory; avoid all skin contact; highly toxic by all routes of exposure
Isolation & Evacuation
First Actions for a UN 2781 Incident
- Call 911 and the emergency response number shown on the shipping papers.
- Keep unauthorized personnel away and establish an initial isolation perimeter.
- Stay upwind, uphill and upstream; avoid low areas where vapors or runoff may collect.
- Avoid breathing vapors, dust, mist or smoke and prevent skin and eye contact.
- Do not touch damaged packages, leaking containers or spilled material without appropriate PPE.
- Ventilate confined spaces only when responders are trained, equipped and monitoring conditions.
- Use ERG, SDS, shipping papers and air monitoring to set final isolation, evacuation and decon actions.
📋 Copy & Share Field Card
UN 2781 — Bipyridilium pesticide, solid, poisonousUse for: Quick radio or face-to-face size-up. Short, structured, field-ready.
Use for: Incident command briefing, staging area whiteboard, or pre-entry team brief.
Use for: Quick text to command or incoming units. Fits in a single SMS.