As the skyscrapers ascend to 40 or 50 stories, crane operators sometimes find themselves above the clouds. Ground crews will then have to direct their movements under cloud level via intercom.
當大樓往上蓋，塔吊手在四、五十層樓高工作時，還會出現「在雲上工作」的奇景，底下只得靠對講機「隔雲指揮」。