49 C.F.R. § 230.38 Telltale holes.
Title 49 - Transportation
(a) Staybolts less than 8 inches long. All staybolts shorter than 8 inches, except flexible bolts, shall have telltale holes 3/16 inch to 7/32 inch diameter and at least 1 (b) Reduced body staybolts. On reduced body staybolts, the telltale hole shall extend beyond the fillet and into the reduced section of the staybolt. Staybolts may have through telltale holes. (c) Telltale holes kept open. All telltale holes, except as provided for in §230.41, must be kept open at all times.
Title 49: Transportation
PART 230—STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS
Subpart B—Boilers and Appurtenances
Staybolts
§ 230.38 Telltale holes.
