[Code of Federal Regulations] [Title 46, Volume 1] [Revised as of January 1, 2007] From the U.S. Government Printing Office via GPO Access [CITE: 46CFR30.10-13] [Page 392] TITLE 46--SHIPPING CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PART 30_GENERAL PROVISIONS--Table of Contents Subpart 30.10_Definitions Sec. 30.10-13 Cofferdam--TB/ALL. The term cofferdam means a void or empty space separating two or more compartments for the purpose of isolation or to prevent the contents of one compartment from entering another in the event of the failure of the walls of one to retain their tightness.