1898 - Coalmininghistorypa.org

No. 11. MINING LAWS OF PENNSYLVANIA. cvli.suitable building material, laid in mortar or cement whenever praclieable, but in no case shall said air stoppings be constructed oiplank except for temporary purposes.Section U. All doors used in assisting or in any way affecting theventilation shall be so hung and adjusted that they will close automatically.Section 10. All main doors shall have aa attendant whose constantduty it shall be to open them for transportation and travel andprevent them from standing open longer than isnecessary for personsor cars to pass through.Section 11.All main doois shall be so placed that when one dooris open, another, which has the same effect upon the same current,.shall be and remain closed and thus prevent any temporary stoppageof the air current.Section 12. An extra main door shall be so placed and kept standingopen, so as to be out of reach of accident, and so fixed that it canbe at once closed in the event of an accident to the doors in use.Section 13. The frame work of such main doors shall be substantiallysecured in stone or brick, laid in mortar or cement unless otherwisepermitted in writing by the inspector.Section 14.All permanent air bridges shall be substantially builtof such material and such strength as the circumstances may reo.uire.Section 15. The quantities of air in circulation shall be ascertainedwith an anemometer or other efficient instrument; suchmeasurements shall be made by the inside foreman or his assistantonce a week at the inlet and outlet airways, also at or near theface of each gangway and at the nearest cross-heading to the face ofeach gangway and at the nearest cross-heading to the face of the insideand outside chamber or breast where men are employed, and•he headings shall not be driven more than sixty (GO)face of each chamber or breast and shall be entered infeet from thethe collieryreport book.Section IG. A report of these air measurements shall be sent to theinspector before the twelfth day of each month, for the precedingmonth, together with a statement of the number of persons employedin each district.Section 17. All ventilators used at mines shall be provided with recordinginstruments by which the speed of the ventilators or the ventilatingpressure shall be registered for each hour, and such datasiiallbe preserved at the colliery for future reference, for a period ofthree months.Section 18. Any person or persons who shall neglect or fail tocomply with the provisions of this article, or who shall make anyfalse report in regard to air measurements, shallbe guilty of an offenseagainst this act.8