[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: 49CFR230.24]

[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. 230.24  Maximum allowable stress.

    (a) Maximum allowable stress value. The maximum allowable stress 
value on any component of a steam locomotive boiler shall not exceed \1/
4\ of the ultimate tensile strength of its material.
    (b) Safety factor. When it is necessary to use the code of original 
construction in boiler calculations, the safety factor value shall not 
be less than 4.