What is the function of millisecond delay devices in blasting operations?

The function of millisecond delay devices in blasting operations is to provide non-electric shot interval delays. These devices allow for precise timing between different charges in a blast, enabling a controlled sequential detonation. This controlled delay reduces the risk of ground vibration and air blast, which can be detrimental to surrounding structures and the environment. Additionally, the use of millisecond delays enhances the fragmentation of rock, improving the overall efficiency of the blasting operation by optimizing the energy distribution of the explosive force.

Other options do not accurately reflect the role of these devices. Surface initiation of blasts pertains to different initiation techniques, while increasing the power of blasting caps and ensuring immediate detonation are not primary functions of millisecond delays. Therefore, the correct choice highlights the key benefit of more effective and safer mining operations through controlled explosive timing.