{"data":{"id":"us/49-cfr-213.137","jurisdiction":"us","citation":"49 CFR 213.137","heading":"Frogs.","body":"(a) Except as provided in paragraph (e) of this section, the flangeway depth measured from a plane across the wheel-bearing area of a frog on Class 1 track shall not be less than 1 3/8 inches, or less than 1 1/2 inches on Classes 2 through 5 track.\n(b) If a frog point is chipped, broken, or worn more than five-eighths inch down and 6 inches back, operating speed over the frog shall not be more than 10 m.p.h.\n(c) If the tread portion of a frog casting is worn down more than three-eighths inch below the original contour, operating speed over that frog shall not be more than 10 m.p.h.\n(d) Where frogs are designed as flange-bearing, flangeway depth may be less than that shown for Class 1 if operated at Class 1 speeds.\n(e) The flange depth requirements in paragraph (a) do not apply to a frog designed as a flange-bearing frog (FBF) used in a crossing diamond in Classes 2 through 5 track, provided that the crossing angle is greater than 20 degrees unless movable guard rails are used.","path":["Title 49—Transportation","Subtitle B—Other Regulations Relating to Transportation","CHAPTER II—FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION","PART 213—TRACK SAFETY STANDARDS","Subpart D—Track Structure"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-49.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:34Z","sha256":"6d09ec0379714b807ea3fab79f42fee69a4bc27b303b84da269f1f381b376208","source_id":"us-cfr","stale":true,"prev":"us/49-cfr-213.135","next":"us/49-cfr-213.139"},"notice":"GroundRules: Original legal text. Not legal advice."}