---
kind: "range"
citation: "49 C.F.R. §§ 236.377–236.380"
title: "49"
from: "236.377"
to: "236.380"
count: 4
url: "https://uscodex.org/cfr/49/236.377..236.380"
---

# §236.377. Approach locking.


Approach locking shall be tested when placed in service and thereafter when modified, disarranged, or at least once every two years, whichever shall occur first.


# §236.378. Time locking.


Time locking shall be tested when placed in service and thereafter when modified, disarranged, or at least once every two years, whichever shall occur first.


# §236.379. Route locking.


Route locking or other type of switch locking shall be tested when placed in service and thereafter when modified, disarranged, or at least once every two years, whichever shall occur first.


# §236.380. Indication locking.


Indication locking shall be tested when placed in service and thereafter when modified, disarranged, or at least once every two years, whichever shall occur first.