[Code of Federal Regulations] [Title 42, Volume 1] [Revised as of October 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 42CFR84.51] [Page 517] TITLE 42--PUBLIC HEALTH CHAPTER I--PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES PART 84_APPROVAL OF RESPIRATORY PROTECTIVE DEVICES--Table of Contents Subpart F_Classification of Approved Respirators; Scope of Approval; Atmospheric Hazards; Service Time Sec. 84.51 Entry and escape, or escape only; classification. Respirators described in subparts H through L of this part shall be classified for use as follows: (a) Entry and escape. Respirators designed and approved for use during entry into a hazardous atmosphere, and for escape from a hazardous atmosphere; or (b) Escape only. Respirators designed and approved for use only during escape from a hazardous atmosphere.