Identify the correct statement.NONEL is used for surface connection of...
**Correct Statement:**
The correct statement is option 'C' - NONEL is used for surface connection of the blast holes in order to provide noiseless shock front movement.
**Explanation:**
NONEL, also known as Non-Electric Detonators, is a type of detonator used in blasting operations. It is often used in surface connection of blast holes, where it provides several advantages, including noiseless shock front movement.
NONEL detonators are typically used in situations where it is necessary to achieve a noiseless or low-noise blasting operation. This can be important in various scenarios, such as near residential areas or sensitive structures where noise can cause disturbances or damage.
The noiseless shock front movement provided by NONEL is achieved through the use of shock tube technology. Shock tube is a flexible plastic tube filled with an explosive material, typically PETN (Pentaerythritol tetranitrate). When the detonator is initiated, a shock wave is generated in the shock tube, which transmits the detonation to the main explosive charge in the blast hole. This shock wave travels faster than the speed of sound in the shock tube, resulting in noiseless shock front movement.
In addition to noiseless shock front movement, NONEL also offers other advantages, such as improved safety and reliability. Unlike electric detonators, NONEL does not require electrical connections, which eliminates the risk of accidental initiation due to electrical currents or stray currents. NONEL also provides better water resistance compared to traditional detonating fuse, which can be beneficial in wet or underwater blasting operations.
Overall, the use of NONEL for surface connection of blast holes helps to achieve noiseless shock front movement, ensuring safer and more controlled blasting operations.