CFR > Title 21 - Food and Drugs > CHAPTER I—FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES > SUBCHAPTER H—MEDICAL DEVICES (parts 800 to 898) > PART 808—EXEMPTIONS FROM FEDERAL PREEMPTION OF STATE AND LOCAL MEDICAL DEVICE REQUIREMENTS > SUBPART B—Exemption Procedures (§808.20 to §808.35)