Final answer:
Dual delay detonators and Nonel detonators are explosive devices used in mining and construction. They differ in their operation and design.
Step-by-step explanation:
Dual delay detonators and Nonel detonators are both types of explosive devices used in mining and construction. However, they differ in their operation and design. Dual delay detonators are used to initiate a series of explosive charges with a time delay between each charge, allowing for controlled blasting. Nonel detonators, on the other hand, are electrically initiated devices that provide a precise and simultaneous ignition of multiple charges. They are commonly used for blasting in underground mining operations.