When blasting at the start of a tunnel or in a portal, several safety measures must be taken to control flyrock and ensure the safety of workers and equipment. First, accurate pre-blast assessments should be conducted to determine the optimal amount of explosive and the correct delay timing to minimise excessive rock movement. Proper confinement techniques, such as adequate stemming and using blast mats or protective barriers, should be employed to contain the blast and prevent flyrock based on

The drill and blast method is a widely used technique in tunnel construction, especially in hard rock environments. This method involves drilling a series of holes into the rock face, filling them with explosives, and then detonating them to break the rock into manageable pieces. After blasting, the debris, known as muck, is removed. Drill and blast is favoured for its effectiveness in excavating through tough geological conditions, but it requires precise planning and control to minimise vibrat