Code of Federal Regulations Title 49. Transportation § 49.299.331 Turnouts and crossings generally

(a) In turnouts and track crossings, the fastenings shall be intact and maintained to keep the components securely in place. Also, each switch, frog, and guard rail shall be kept free of obstructions that may interfere with the passage of wheels. Use of rigid rail crossings at grade is limited to track Classes H0, H1, and H2.

(b) The track through and on each side of track crossings and turnouts shall be designed to restrain rail movement affecting the position of switch points and frogs.

(c) Each flangeway at turnouts shall be at least 39 mm (1.5 inches) wide.

(d) For all turnouts and track crossings, the railroad shall prepare inspection and maintenance requirements to be included in the railroad's inspection, testing, and maintenance program.