| # | Concept | Culture | Statement | Freq. |
|---|---|---|---|---|
| 1 | revolving door | Europe | Revolving doors are popular in Europe for energy efficiency and airflow regulation in urban and commercial buildings. | 5 |
| 2 | revolving door | United States | Revolving doors are popular in the US for energy efficiency and regulating airflow in high-traffic buildings. | 5 |