30 CFR § 75.210 Manual installation of temporary support.
(a) When manually installing temporary support, only persons engaged
in installing the support shall proceed beyond permanent support.
(b) When manually installing temporary supports, the first temporary
support shall be set no more than 5 feet from a permanent roof support and
the rib. All temporary supports shall be set so that the person installing
the supports remains between the temporary support being set and two other
supports which shall be no more than 5 feet from the support being
installed. Each temporary support shall be completely installed prior to
installing the next temporary support.
(c) All temporary supports shall be placed on no more than 5-foot
(d) Once temporary supports have been installed, work or travel
beyond permanent roof support shall be done between temporary supports and
the nearest permanent support or between other temporary supports.