49 CFR 234.203 : Transportation (§ 1.1 To Parts 1581-1699) — (§ 200.1 To Parts 273-299) — Other Regulations Relating To Transportation (Continued) (§ 200.1 To Parts 273-299) — Federal Railroad Administration, Department Of Transportation (§ 200.1 To Parts 273-299) — Grade Crossing Safety (§ 234.1 To Appendix B To Part 234) — Maintenance, Inspection, And Testing (§ 234.201 To § 234.275) — Maintenance Standards (§ 234.201 To § 234.245) — Control circuits.
4 Aug 2016
All control circuits that affect the safe operation of a highway-rail grade crossing warning system shall operate on the fail-safe principle.