Regulations last checked for updates: Feb 07, 2026

Title 49 - Transportation last revised: Feb 03, 2026
§ 236.309 - Loss of shunt protection; where required.

(a) A loss of shunt of 5 seconds or less shall not permit an established route to be changed at an automatic interlocking.

(b) A loss of shunt of 5 seconds or less shall not permit the release of the route locking circuit of each power-operated switch hereafter installed.

[49 FR 3385, Jan. 26, 1984]
source: 33 FR 19684, Dec. 25, 1968, unless otherwise noted.
cite as: 49 CFR 236.309