根据《水利水电工程施工通用安全技术规程》(SL398-2007),明挖爆破的预告信号为间断鸣三次长声,即()。
A、鸣20s、停、鸣20s、停、鸣20s
B、鸣10s、停、鸣10s、停、鸣10s
C、鸣10s、停、鸣20s、停、鸣30s
D、鸣30s、停、鸣30s、停、鸣30s
发布时间:2023-08-09 23:27:56
A、鸣20s、停、鸣20s、停、鸣20s
B、鸣10s、停、鸣10s、停、鸣10s
C、鸣10s、停、鸣20s、停、鸣30s
D、鸣30s、停、鸣30s、停、鸣30s