Final answer:
The Bomb squad should be used to clear the crime scene prior to personnel entering and conducting investigations in the case of an explosion.
Step-by-step explanation:
In any case where an explosion has occurred, the Bomb squad should be used to clear the crime scene prior to personnel entering and conducting investigations. The Bomb squad is specifically trained to handle explosive devices and ensure the safety of the area. They use specialized equipment, such as bomb-detection robots and bomb suits, to safely locate and defuse any unexploded bombs or second devices that may be present.