Final answer:
To find out the type of biometric readers used to unlock the PSL doors, one must refer to the facility's specific security details, which usually involve a range of biometric devices like fingerprint scanners, facial recognition systems, iris scanners, and hand geometry readers, with fingerprint scanners being the most commonly adopted for their convenience and security.
Step-by-step explanation:
To determine which biometric readers unlock the PSL doors, we would need access to specific information about the security system installed in that particular facility. Biometric readers come in various forms such as fingerprint scanners, facial recognition systems, iris scanners, and hand geometry readers. The most common type which is widely used due to its balance between security and convenience is the fingerprint scanner.
These systems work by comparing the scanned biometric data with stored data to confirm a person's identity. For instance, a fingerprint scanner will analyze specific patterns in an individual's fingerprint to allow access. It is important to note that for security purposes, the details of such systems are typically not disclosed publicly.
If this question pertains to a specific building or institution, the best approach would be to consult the institution's security office for accurate information regarding their security measures and the type of biometric reader they use.