UN 0378 — Primers, cap type
Placard: Explosive 1.4B. ERG Guide 114. Training/quick-reference only — use current ERG + SOP/SOG for incident-specific actions.
UN 0378 is Primers, cap type, a Class 1.4 explosive article assigned to ERG Guide 114. It is a limited-effect initiator-type article, but heat, shock, static or damage can still create a dangerous localized blast hazard.
Hazard overview: UN 0378 presents a localized initiator hazard. Heat, impact, friction, static, electrical energy or mechanical disturbance may cause popping, deflagration or small blast effects, and grouped articles can still injure nearby personnel.
Response guidance: For a UN 0378 incident, responders should confirm the article using shipping papers, markings and ERG Guide 114. Isolate the area, avoid disturbing leads or damaged units, control ignition and static sources when safe, and request explosive specialists if condition or quantity is uncertain.
Firefighter training notes: Training should emphasize the difference between 1.4 limited-effect explosives and higher-hazard Class 1 materials. Common errors include standing too close to heated packages, dismissing smoke hazards, disturbing damaged articles and failing to check for adjacent explosives or ammunition.
Regulatory context: Primers, cap type is regulated as a Class 1 explosive article for transportation. Storage, quantity limits, fire code controls and reporting requirements may vary by jurisdiction. Responders should verify current requirements through shipping papers, product documents and applicable DOT, ATF, OSHA, NFPA or local authority guidance.
Storage & handling: Primers, cap type should be stored in compatible packaging away from heat, sparks, open flame, impact and unauthorized access. Keep separated from incompatible explosives, propellants and combustible clutter according to product instructions and local fire code.
UN 0378 Quick Details
Common Hazards of UN 0378
- Minor explosive hazard with localized blast, popping or fragment effects possible if initiated.
- Detonators, primers, fuzes or igniters may be sensitive to heat, impact, friction, static or electrical energy depending on design.
- Smoke and heat from burning articles may irritate the eyes and respiratory tract.
- Low mass explosion risk under normal transport conditions, but grouped articles can still injure nearby personnel.
- Heated packages may fail and scatter small articles or fragments.
- Nearby explosives, ammunition or pyrotechnics may increase the overall incident hazard.
Chemical Identity & Physical Properties
Small metallic cups or cylinders containing a small amount of impact-sensitive explosive mixture. Typically brass, copper, or aluminum construction with pressed explosive compound inside.
| Also known as | percussion capsprimer capsblasting capsignition primersdetonator caps |
| Appearance | Small metallic cups or cylinders containing a small amount of impact-sensitive explosive mixture. Typically brass, copper, or aluminum construction with pressed explosive compound inside. |
| Flash Point | Not applicable (explosive device) |
| Boiling Point | Not applicable (explosive device) |
| Vapor Density | Not applicable (solid device) |
| Water Reactivity | No significant reaction with water, though water may be used for cooling or containment |
Fireground Response Guidance — UN 0378
Extinguishing Media
PPE Requirements
Structural firefighting protective clothing with SCBA is appropriate for fire or smoke exposure, with distance maintained from heated packages. Approach and handling should follow incident command and local SOP.
Isolation & Evacuation
First Actions for a UN 0378 Incident
- CALL 911. Notify law enforcement if ammunition components, explosive articles or ordnance are involved.
- Keep unauthorized personnel away.
- Stage upwind and avoid smoke from burning articles.
- Avoid radios, static sources, electrical leads or mechanical disturbance around suspected initiators unless cleared by specialists.
- Eliminate ignition sources if it is safe to do so.
- Isolate the area and expand the perimeter if fire grows or additional explosives are present.
- Use ERG Guide 114, shipping papers and incident command for isolation and fire response decisions.
📋 Copy & Share Field Card
UN 0378 — Primers, cap typeUse 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.