[Code of Federal Regulations] [Title 46, Volume 2] [Revised as of October 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 46CFR64.67] [Page 322] TITLE 46--SHIPPING CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PART 64_MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS--Table of Contents Subpart C_Pressure Relief Devices and Vacuum Relief Devices for MPTs Sec. 64.67 Shutoff valve. A shutoff valve may not be located-- (a) Between the tank opening and pressure relief device; or (b) On the discharge side of the pressure relief device.