There are three main factors involved when it comes to cleaning skyscraper windows: cleaning equipment, cleaning mechanism technology and environmental considerations. Due to the epic heights and natural factors like wind involved in the operation, every cleaner is equipped with a harness, descent and safety rope, rope protector, rope-grabbing tool, descent mechanism, lanyard and suction cups. Together these tools enable the worker to negotiate a building’s vertical facade at speed, while attached to a roof-mounted anchor. This anchor allows cleaners to descend in ‘drops’ – the measurement of one vertical cleaning operation from roof to the below floor or platform – without fear of falling.
When group work is necessary, a cleaning mechanism will be employed (see boxout on the right for more information). These mechanical gantries enable teams of cleaners to work in unison and are powered by roof-mounted hydraulic and pneumatic support systems. The ascending and descending of the gantries is dictated by a control panel, but as a backup additional control systems are typically placed on the roof of the building.
Lastly, when cleaning sky scraper windows, workers must constantly be vigilant of potentially deadly environmental factors – the chief one being wind. At the high altitude of skyscrapers, wind flow is not just fierce but highly turbulent, with the building acting as a disrupter to the general environmental flow. These gusts can blow cleaners off course, cause tools to be dropped (a risk to anyone passing below) and render gantries unusable. Luckily, many modern skyscrapers – such as the world’s tallest, the Burj Khalifa in Dubai – are now being designed to smoothly redirect winds around their structures and prevent the buildup of vortices and turbulence.