近年来，建筑行业事故频发，伤亡触目惊心。因此，在涉及安全的工程、建筑、设施及有关场合设立安全指数倒计时板很有必要。所谓安全指数倒计时板，就是在易发生危险、伤亡事故的桥梁、车船、楼宇、商厦、剧场、车站、影院、厂房、公路等建筑、生产和娱乐设施的显著位置上，由? In recent years, accidents in the construction industry have caused a lot of casualties. Therefore, it is necessary to establish a safety index countdown plate in engineering, construction, facilities and related situations involving safety. The so-called safety index countdown board is a prominent place on the bridges, vehicles, buildings, commercial buildings, theaters, stations, cinemas, factories, highways and other buildings, production and entertainment facilities that are prone to danger and casualties.