UN 3549 — Medical waste, category A, affecting animals only, solid
Placard: Infectious Substance. ERG Guide 158. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 3549 is Medical waste, category A, affecting animals only, solid, assigned to ERG Guide 158. This entry should be verified with shipping papers, labels and the SDS before responders commit to close-range action.
Hazard overview: Medical waste, category A, affecting animals only, solid has article-specific hazards that depend on the contained material. Damaged articles, heat, pressure, smoke or exposed contents may increase risk.
Response guidance: Use ERG Guide 158, confirm the exact contents, isolate the area, keep unauthorized personnel away, control ignition sources and choose extinguishing agents based on the article or material involved.
UN 3549 Quick Details
Common Hazards of UN 3549
- Inhalation or contact with substance may cause infection, disease or death.
- Category A Infectious Substances (UN2814, UN2900 or UN3549) are more hazardous, or are in a more
- Runoff from fire control or dilution water may cause environmental contamination.
- Damaged packages containing solid CO2 as a refrigerant may produce water or frost from condensation
- Contact with solid CO2 may cause burns, severe injury and/or frostbite.
- Some of these materials may burn, but none ignite readily.
- Some may be transported in flammable liquids.
Chemical Identity & Physical Properties
Solid medical waste materials contaminated with Category A infectious substances affecting animals only. May include tissues, specimens, cultures, or contaminated items in various physical forms and colors.
| Also known as | Category A infectious waste affecting animalsRegulated medical waste UN3549Animal pathogen wasteVeterinary infectious wasteSolid biohazardous animal waste |
| Appearance | Solid medical waste materials contaminated with Category A infectious substances affecting animals only. May include tissues, specimens, cultures, or contaminated items in various physical forms and colors. |
| Flash Point | Not applicable (non-flammable infectious waste) |
| Boiling Point | Not applicable (solid waste mixture) |
| Vapor Density | Not applicable (solid material) |
| Water Reactivity | No significant reaction with water, but runoff may cause biological contamination |
Fireground Response Guidance — UN 3549
Extinguishing Media
PPE Requirements
Level B minimum with SCBA required; impermeable suits, double gloves, eye/face protection; prevent any contact with material to avoid infection or disease transmission. Select final PPE using ERG guidance, SDS, monitoring and incident command.
Isolation & Evacuation
First Actions for a UN 3549 Incident
- Keep unauthorized personnel away.
- Stay upwind, uphill and/or upstream.
- Consult the shipping paper to identify the substance involved.
- Isolate spill or leak area for at least 25 meters (75 feet) in all directions.
📋 Copy & Share Field Card
UN 3549 — Medical waste, category A, affecting aniUse 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.