求翻译：在户外：要避开高大建筑物，要远离高压线及石化、化学、煤气等有毒的工厂或设施。在过桥时应紧紧抓住桥栏杆，待主震发生后即向桥头移动，正在行驶的车辆应紧急刹车。是什么意思？

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Outdoor: It is necessary to avoid the tall buildings, to stay away from high voltage and petrochemical, chemical, gas, and other toxic plants or facilities. When the bridge should be seized to be main quake occurred, bridge railings to Qiaotou mobile, moving vehicles should be emergency braking.

In outdoors: Must avoid the big building, must be far away the high tension line and the petrification, chemistry, the coal gas and so on the virulent factory or the facility.When bridge should closely hold the bridge railing, after waits the principal earthquake to occur namely moves to the bridge

In the open air: to avoid tall buildings, to stay away from high voltage wire and petrochemical, chemical, gas and other toxic plants or facilities. At the time of the bridge should firmly grasp the railing of the bridge, after the main earthquake occurred that move in the bridgehead, was travelling

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