Possible Clues:

• Practice for a future conflagration
• Grade-school ritual
• Sack doctor not good for practice for disaster
• Emergency simulation that might interrupt class
• Safety exercise prompted by an alarm
• Safety exercise
• Anger director going into superfluous detail in safety exercise
• School exercise involving leaving one's seat
• If up against burning trench, this could be needed
• Female about to go to doctor, unwell -- one admitted for emergency procedure