UN 0055 — Cases, cartridge, empty, with primer
Placard: Explosive 1.4S. ERG Guide 114. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 0055 refers to empty metallic cartridge cases, typically brass or steel, that contain a live percussion primer but no propellant or projectile. Despite their limited explosive classification under Division 1.4S, these primed casings can produce localized deflagration, heat, and smoke if exposed to fire.
Hazard overview: UN 0055 presents a minor blast and fire hazard due to the percussion primer, which can ignite and cause localized burning or deflagration under heat exposure. Smoke produced from burning primers may contain toxic combustion byproducts and should not be inhaled.
Response guidance: Emergency responders should isolate the area a minimum of 25 meters in all directions, increasing to an 800-meter evacuation radius in the event of a large fire. Water spray or fog is acceptable for fire control, and structural firefighting gear provides adequate protection for standard response operations.
UN 0055 Quick Details
Common Hazards of UN 0055
- Minor blast or fire hazard — limited effect.
- Localized burning or deflagration possible.
- Smoke and heat from burning.
- Low mass explosion risk under normal conditions.
Chemical Identity & Physical Properties
UN 0055 cartridge cases appear as empty brass or steel shell casings with the primer cup intact at the base, containing no propellant charge or projectile.
| Also known as | Empty cartridge cases with primerPrimed cartridge casesEmpty brass with primersSpent cartridge cases with live primers |
| Appearance | Metallic cartridge cases (typically brass or steel) containing only a percussion primer, no propellant or projectile. Appear as empty shell casings with primer cup intact at base. |
| Flash Point | Not applicable (explosive article) |
| Boiling Point | Not applicable (metal article) |
| Vapor Density | Not applicable (solid article) |
| Water Reactivity | No significant reaction with water |
Fireground Response Guidance — UN 0055
Extinguishing Media
PPE Requirements
Standard structural firefighting gear is adequate for responding to UN 0055 incidents, though responders must avoid inhaling smoke generated by burning percussion primers.
Isolation & Evacuation
First Actions for a UN 0055 Incident
- CALL 911. Notify law enforcement.
- Isolate area; keep unauthorized personnel away.
- Stage upwind; eliminate ignition sources.
- Request Hazmat + law enforcement.
- Consult current ERG Guide 114 and follow SOP/SOG.
📋 Copy & Share Field Card
UN 0055 — Cases, cartridge, empty, with primerUse 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.