.井下防爆电气设备的运行、维护和修理,必须符合防爆性能的技术要求。防爆性能遭受破坏的电气设备,必须立即处理或更换,严禁继续使用
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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