4VAC25-60-70. Minimum requirements for machines using, or used as, automated temporary roof support systems.
A. All machines using, or used as, an ATRS system shall comply with the following minimum requirements unless a waiver has been granted by the Chief.
B. The controls to position the machine and place the ATRS system against the roof shall be operated from under permanently supported roof, or the controls may be located in a compartment which includes a deck that provides the equipment operator with overhead and lateral protection, and has the structural capacity to elastically support a dead weight load of at least 18,000 pounds.
C. The ATRS system shall be placed firmly against the roof before any work is performed inby permanent roof supports and shall remain against the roof while work is being done.
D. All hydraulic jacks affecting the support capacity of an ATRS system shall have check valves or equivalent protection to prevent support failure in the event of a sudden loss of hydraulic pressure.
E. ATRS systems used in conjunction with single bolt installation are required to elastically support, at a minimum, a deadweight load measured in pounds of at least 450 times each square foot of roof intended to be supported, but in no case less than 11,250 pounds.
F. The actual capacity to elastically support a deadweight load shall be certified by a registered engineer. Documentation of the certification of the ATRS system shall be made available to the Chief or his authorized representative.
G. The distance that the ATRS system may be set inby the last row of permanent supports shall be dependent on the spacing requirements of the permanent roof supports and must be approved by the Chief or his authorized representative in the approved roof control plan.
H. No person shall work or travel beyond the ATRS system unless the distance between the coal face and the ATRS system is five feet or less. In addition, no person shall work or travel left or right of the ATRS unless a coal rib, a permanent support, or a temporary support is within five feet of the ATRS system. The only exception is that when a five foot limit is being measured from an ATRS system consisting of a ring, then the five foot limit shall be determined from the outside of the ring.
I. In no case shall the inch tram control speed exceed 80 feet per minute when the roof bolting machine is being used to establish the ATRS system.
Statutory Authority
§§ 45.1-161.3, 45.1-161.106 and 45.1-161.114 of the Code of Virginia.
Historical Notes
Derived from VR480-05-3, Part IV, eff. December 11, 1985; amended, Virginia Register Volume 15, Issue 22, eff. August 18, 1999.