49 C.F.R. § 213.65 — Combined track alinement and surface deviations.
§ 213.65 Combined track alinement and surface deviations. On any curved track where operations are conducted at a qualified cant deficiency, E u , greater than 5 inches, the combination of alinement and surface deviations for the same chord length on the outside rail in the curve, as measured by a TGMS, shall comply with the following formula: ER13MR13.008 Where— A m = measured alinement deviation from uniformity (outward is positive, inward is negative). A L = allowable alinement limit as per § 213.55(b) (always positive) for the class of track. S m = measured profile deviation from uniformity (down is positive, up is negative). S L = allowable profile limit as per § 213.63(b) (always positive) for the class of track. ER13MR13.009 [78 FR 16102, Mar. 13, 2013]