[Code of Federal Regulations] [Title 49, Volume 4] [Revised as of October 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 49CFR230.26] [Page 380] TITLE 49--TRANSPORTATION CHAPTER II--FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PART 230_STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS--Table of Contents Subpart B_Boilers and Appurtenances Sec. 230.26 Tensile strength of shell plates. When the tensile strength of steel or wrought-iron shell plates is not known, it shall be taken at 50,000 psi for steel and 45,000 psi for wrought iron.