Final answer:
The Health Insurance Portability and Accountability Act (HIPAA) allows patients to request restrictions on the use and disclosure of their Protected Health Information (PHI) for Treatment, Payment, and Operations (TPO) purposes.
Step-by-step explanation:
The act that allows patients to request restrictions of PHI (for TPO purposes) is the Health Insurance Portability and Accountability Act (HIPAA). HIPAA sets the standards for the protection of patient information and requires healthcare providers to maintain strict confidentiality of patient records. Patients can request restrictions on the use and disclosure of their Protected Health Information (PHI) for Treatment, Payment, and Operations (TPO) purposes. The circumstances in which patients can request restrictions may include situations where they do not want certain information to be shared with specific individuals or entities.