56. Before starting any maintenance work on a track, the foreman who is in charge of the work must protect the track as follows:
(1) each switch must be locked with a padlock, to which he is the only one to have the key, in the position that prevents access to the track in question; or
(2) place a stop signal between the rails at the ends of the working limits; the signal consists of a red flag and a monitoring system.
The signal referred to in subparagraph 2 of the first paragraph must be set up on staffs at a height that ensures a clear view thereof from the equipment. It may not be removed without the foreman’s authorization.