Final answer:
After a thorough search by ISP personnel, if no bomb is found, the person in charge is informed that no evidence of a bomb was found, mitigating the threat and allowing the institution to resume normal activities or take further action.
Step-by-step explanation:
If ISP personnel have been called to the scene of a bomb threat in a building and have performed a thorough search according to procedure, and no bomb or suspected bomb is discovered, the person in charge of the institution will be informed that 'no evidence of a bomb was found.' This outcome relieves immediate concerns of a serious fire or hazard after the alert, mitigates the potential for extreme physical danger, and allows for the resumption of normal operations or further investigation if necessary.