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Underground incubator: How germy is Metro?
What happens when thousands of people hold the same handrails, hike up the same escalators and punch the same farecard buttons every day? A team of TBD researchers attempts to find out.
Starting line: Rosslyn
The team debated the most-touched buttons on the SmarTrip machine, settling on the "add value" button.
(Photo: Heather Farrell/TBD | Date: Feb. 07, 2011)
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