I wanted to draw attention to how a clean looking data hall floor can actually be very deceiving. The first picture here shows the data hall floor in question. I am sure you will agree, it looks clean? Picture two shows the pad used to buff this section of floor. After the buffing we used a tack wipe to wipe the floor. The floor was in fact covered in a very fine/sub micron dust particulate matter (PM), which almost certainly has been walked and wheeled into the data hall. The dust was being held on the floor by one of van de Waals forces, probably London Dispersion Force. A paper in 2014 by “Cher Lin Clara Tan , Shaokai Gao , Boon Siong Wee , Akua Asa-Awuku & Beng Joo Reginald Thio (2014) Adhesion of Dust Particles to Common Indoor Surfaces in an Air-Conditioned Environment . Showed this was the case in office environments, so I am sure it is also true in air conditioned data halls. This dust will remain on the floor until it is disturbed, by lifting a tile etc. Then it will once again become airborne and is free to travel in to the equipment via the airflow. Once again this show how important it is to have regular cleaning of your data hall. Harmful particulate dust (PM) can hide in plain site.
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