Final answer:
After breaking a window for entry, a firefighter should clear the entire window area of glass to ensure safety and maintain a clear exit point.
Step-by-step explanation:
Once a firefighter has broken a window for entry, the next action should be to clear the entire window area of glass. This is a critical safety measure to prevent injury from jagged edges while entering the building and to secure a safe exit point. Given the unpredictable nature of fires, maintaining a clear area of glass is essential for both the firefighter and potential victims needing rescue. Firefighters must be equipped with appropriate personal protective equipment (PPE), such as fire-resistant clothing and breathing apparatus, for their own safety during these operations.