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Stampede-proof staircase wins national patent

(chinadaily.com.cn) Updated: 2012-11-30 16:08

Stampede-proof staircase wins national patent 

Liu Hao, a junior high student in Changsha city, Central China's Hunan province, shows his national patent-winning invention, a stampede-proof staircase, on Nov 29, 2012. The staircase can be adjusted with a movable handrail so that it is narrow on top and wide at the bottom, which effectively controls the number of people going down and also accelerates the flow of people, thus preventing stampedes. [Photo/asianewsphoto] 

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