火災

1. Origins, structure, and basic meaning

• Structure: 火災 is read as かさい and is a noun for a fire incident in a building or facility that can endanger people or property.
• Basic usage: Use 火災を想定する for a simulated emergency, 倉庫の火災 for its location, and 火災を消し止める for extinguishing it.

2. Common pitfalls and similar expressions

• Flame versus fire incident
  • 火 broadly names fire itself, while 火災 identifies a hazardous incident requiring evacuation or firefighting.
• Drill and actual event
  • The evacuation drill assumes a fire, whereas the warehouse sentence reports an actual incident that was extinguished.