1. Every prop shall be set securely on a sound foundation and shall be kept tight against the roof.
2. Where a prop is set on sand or, other loose material, a flat base-piece not less than 5 centimeter in thickness, 25 centimeters in width and 75 centimeters in length shall be used.
3. The lid used over a prop shall have a width not less than the diameter of the prop, a thickness not less than 8 centimeters and a length not less than 50 centimeters.
4. Every bar set for supporting the roof of a roadway shall be set securely on props or on cogs or shall be securely fixed on the sides of the roadway in holes at least 50 centimeter deep made in the sides of the roadway and shall be made and kept tight against roof and where lagging is necessary the number of laggings shall not be less than one for every meter length of the bar and the laggings shall be made and kept tight against the roof.
5. Every cog used as a support shall be well built and set on the natural floor or on a secure foundation, and shall be made and kept tight maintaining maximum possible contact against the roof.
6. In case of timber for erection of a cog, it shall be sufficient to joggle two opposite sides, provided that only four sides sawn sleepers shall be used for goaf edge supports in depillaring panels.
7. The cogging members shall be not less than 1.2 meters in length.
8. Before erecting cogs in a depillaring area, props shall be erected at the corners of each cog.
9. In inclined seams, the supporting props and cogs shall be so set as to ensure maximum support having regard to the inclination of the seam or roadway and probable strata movement and where necessary such supports shall be reinforced to prevent displacement.
10. Every ledge and every prominent crack or slip in the roof shall be kept supported with at least a pair of cogs and or cross-bars suitably lagged.
11. Overhanging sides shall be dressed down:
Provided that where this is not practicable, stay props or other suitable means of support shall be erected at intervals not exceeding one meter.
12. Where sand or other material is stowed or a pack is formed for the purpose of support, it shall be packed or made as tight against the roof as practicable over its whole area.
13. Roof and sides and support shall be tested as often as necessary; and except where it is no longer necessary for the purpose of support, any support loosened, broken or dislodged by or removed in any operation shall be tightened, replaced or reset with the least possible delay and particularly before persons are allowed to pass or resume work after an interruption.
14. Where floor coal or roof coal is taken, shorter props shall be replaced with longer props.
15. In every place wherein roof coal is taken or a fall of roof or sides has occurred, no work of cleaning the dislodged coal or the fall or any part thereof shall be undertaken nor shall any person be allowed to pass, until the newly exposed roof and sides in the vicinity thereof have been examined and made safe, if necessary, by temporary supports.
16. Notwithstanding anything contained in sub-regulation (9), (13), (14) or sub-regulation (15), only such minimum number of persons may be engaged under the supervision of a sirdar or overman as may be necessary for securing the roof and sides thereat.
17. Where roof bolts are used for support, the bolts shall be securely fixed in place.
18. Powered supports, hydraulic chocks or link-bars shall be advanced as soon as practicable after a web of coal has been taken off the face so as to ensure that the area of unsupported newly exposed roof is kept to a minimum.
19. Powered supports, hydraulic chocks, props and friction props shall be set securely and checked from time to time.
20. When any defect is detected in any powered support or hydraulic chock, the same shall be attended to as soon as possible and any defective hydraulic or friction prop shall be replaced immediately.
21. Where, by reason of any irregularity in the roof, floor or sides or due to any other reasons, any powered support or hydraulic chock becomes ineffective, conventional supports in sufficient number shall be used.
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