---
kind: "section"
citation: "49 C.F.R. § 213.137"
title: "49"
number: "213.137"
heading: "Frogs."
url: "https://uscodex.org/cfr/49/213.137"
---

# §213.137. Frogs.

- (a) Except as provided in [paragraph (e)](#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.
- (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.
- (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.
- (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.
- (e) The flange depth requirements in [paragraph (a)](#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.

## Notes

### Amendments

[63 FR 34029, June 22, 1998, as amended at 85 FR 63388, Oct. 7, 2020]

### Authority

Authority: 49 U.S.C. 20102-20114 and 20142; 28 U.S.C. 2461 note; and 49 CFR 1.89.

### Source

Source: 63 FR 34029, June 22, 1998, unless otherwise noted.

### Amendments

[63 FR 34029, June 22, 1998, as amended at 85 FR 63388, Oct. 7, 2020]