42 CFR § 493.905
Nonapproved proficiency testing programs
June 11, 2020
If a proficiency testing program is determined by HHS to fail to meet any criteria contained in §§493.901 through 493.959 for approval of the proficiency testing program, CMS will notify the program and the program must notify all laboratories enrolled of the nonapproval and the reasons for nonapproval within 30 days of the notification.