非ひ常じょうベル

noun

alarm bell; emergency alarm

Refers to a bell or audible alarm used in emergencies, such as fire alarms or security alerts.

• 火か事じが起おきたら、すぐに非ひ常じょうベルを鳴ならしてください。

  If a fire breaks out, please sound the emergency alarm immediately.

• 非ひ常じょうベルが突とつ然ぜん鳴なり出だして、みんな驚おどろいた。

  The alarm bell suddenly went off and everyone was surprised.