[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: 46CFR56.50-20] [Page 195-196] TITLE 46--SHIPPING CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PART 56_PIPING SYSTEMS AND APPURTENANCES--Table of Contents Subpart 56.50_Design Requirements Pertaining to Specific Systems Sec. 56.50-20 Pressure relief piping. (a) General. There must be no intervening stop valves between the vessel or piping system being protected and its protective device or devices, except as specifically provided for in other regulations or as specifically authorized by the Marine Safety Center. (b) Discharge lines (reproduces 122.6.2(d)). Discharge lines from pressure-relieving safety devices shall be designed to facilitate drainage. [[Page 196]] (c) Stop valves. Stop valves between the safety or relief valve and the point of discharge are not permitted, except as specifically provided for in other regulations or as specifically approved by the Marine Safety Center. (d) Reference. See also Sec. 56.07-10(a) and (b) for specific requirements. [CGFR 68-82, 33 FR 18843, Dec. 18, 1968, as amended by CGFR 69-127, 35 FR 9979, June 17, 1970; CGD 77-140, 54 FR 40607, Oct. 2, 1989]