(d)On hearing the sound of the alarm, the warders in charge of gangs outside the jail shall collect their prisoners and march them to a pre-arranged place where a sufficiency of belchains shall be disposed during working hours. The prisoners shall sit in single file and the chain having been passed through their ankle rings shall be secured by locking. The lock may remain at all times on one end of the chain, but the key, whether a parade is in progress or not, shall remain with the senior warder in charge of the gang.
