49 CFR §230.24
Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
- (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.