A sticky mat, also called a tacky mat or cleanroom mat, is a mat with an adhesive surface that is placed at the entrances or exits to certain workplaces to remove contaminants from the bottoms of footwear and wheeled carts such as hand trucks. Sticky mats are typically used in cleanrooms and construction sites.Their purpose is to prevent contaminants from entering the site with personnel, and hazardous materials from exiting. In a cleanroom setting, airborne particles that are not removed by the ventilation system deposit themselves onto a surface, where they can be transported by personnel walking on or past them.