Final answer:
Instruments exposed to blood in a salon service require disinfection to remove potential pathogens and prevent the transmission of infections.
Step-by-step explanation:
The correct level of infection control for instruments that may have been exposed to blood during a salon service is disinfection. Disinfection is essential for removing potential pathogens from instruments, commonly known as fomites, to prevent the possible transmission of infections. Items that are contaminated with blood and could come into contact with broken skin or mucous membranes are classified as semicritical items and need high-level disinfection to ensure the safety and prevention of infections such as HBV (Hepatitis B virus).