电梯口有警告牌吗？

全美国的扶手式电梯的事故都在增加

http://www.americanownews.com/story/19967395/escalator-accidents-are-climbing

http://crocsaccidents.blogspot.com/

http://well.blogs.nytimes.com/2007/12/12/kids-crocs-and-escalators/?_r=0

http://consumerist.com/2007/09/06/children-crocs-and-escalators-combine-to-produce-mangled-feet/