[Code of Federal Regulations] [Title 21, Volume 8] [Revised as of April 1, 2002] From the U.S. Government Printing Office via GPO Access [CITE: 21CFR866.2850] [Page 242] TITLE 21--FOOD AND DRUGS CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) PART 866--IMMUNOLOGY AND MICROBIOLOGY DEVICES--Table of Contents Subpart C--Microbiology Devices Sec. 866.2850 Automated zone reader. (a) Identification. An automated zone reader is a mechanical device intended for medical purposes to measure zone diameters of microbial growth inhibition (or exhibition), such as those observed on the surface of certain culture media used in disc-agar diffusion antimicrobial susceptibility tests. The device aids in decisionmaking respecting the treatment of disease. (b) Classification. Class I (general controls).