A drill is a low-level exercise that tests, develops, or maintains skills in a single incident response procedure. A drill:

• Is a coordinated, supervised activity usually used to validate a specific operation or function in a single agency or organization.
• May be part of a training program to provide instruction on new equipment, develop or validate new policies and procedures, or maintain current skills.
• Has a narrow focus but is conducted within a realistic environment.
• Provides instant feedback using established standards to measure performance.
• May be used to prepare personnel for larger scale exercises.