[Code of Federal Regulations] [Title 45, Volume 1] [Revised as of October 1, 2006] From the U.S. Government Printing Office via GPO Access [CITE: 45CFR3.21] [Page 13] TITLE 45--PUBLIC WELFARE SUBTITLE A--DEPARTMENT OF HEALTH AND HUMAN SERVICES PART 3_CONDUCT OF PERSONS AND TRAFFIC ON THE NATIONAL INSTITUTES OF HEALTH FEDERAL ENCLAVE--Table of Contents Subpart B_Traffic Regulations Sec. 3.21 Emergency vehicles. A person must yield the right of way to an emergency vehicle operating its siren or flashing lights.