Which type of door is commonly found in upscale buildings in large cities and should be avoided in forcible entry whenever possible?

Revolving doors are commonly found in upscale buildings and serve both aesthetic and functional purposes, providing a barrier against weather conditions and helping to control building temperature. They also serve as an attractive entry point that enhances the building's upscale appearance. However, in emergency situations, especially during forcible entry by firefighters, revolving doors can pose significant challenges.

These doors are designed to minimize airflow when entering or exiting a building and typically require specific actions to operate correctly. Attempting forcible entry may not only be time-consuming but can also lead to complications, such as getting trapped inside the revolving mechanism. Therefore, firefighters are trained to avoid engaging with revolving doors unless absolutely necessary, opting instead for other entry points that are more accessible and quicker to operate, thereby ensuring a more efficient response effort.