What type of sensor might be employed in an access control system?

A motion sensor is an integral component of an access control system because it detects movement within a specified area. This functionality allows the system to ascertain whether an individual is present or if a space is secure, making it essential for triggering alerts or actions based on detected movements.

In access control scenarios, motion sensors enhance security by monitoring for unauthorized access or potential breaches. They can be strategically placed around entry points to provide real-time information about who is entering or exiting a facility. This capability is especially crucial in environments where security is a high priority, such as offices, banks, and secure facilities.

The other types of sensors mentioned, while useful in their respective applications, do not directly provide the same level of security control in an access system. Pressure sensors might gauge weight or force but do not track movement. Temperature sensors monitor environmental conditions rather than presence or movement. Sound sensors detect audio levels or variations but are less reliable for security purposes compared to motion detection technology.