Show METAL MINE DOORS the results of an investigation of fire and ventilation doors in metal mines made by daniel harrington b supervising supervision mining in 6 engineer department of interior are given as follo follows W s in serial 2426 recently issued by the bureau of mines 1 mine doors and their frames should be substantially constructed should be covered with roofing iron or otherwise fire proofed should be tight and should always be kept in repair I 1 2 doors should close automatically after passage of men or cars and should have a latch or other positive means of keeping them closed 3 every main air course whether shaft incline or level should have in place either within itself or in all the openings leading f from roni it a system of doors such that irr incase case of emergency the entire shaft incline or level opening 6 can be quickly isolated from other parts of the mine this is especially important as to downcast or intake timbered shafts inclines or level air courses doors should be provided for or all openings leading from main air courses both intake and return and when at ordinary times there should be free flow of air the door should have a sign denoting that it is to be closed only in case of emergency if possible giving b the exact connig contingency conti gency under tinder which the door should be closed 4 all doors but especially those for fire purposes or for use in exits between mines should close flush against the face of doorframe instead of in a groove within the frame this is to prevent sticking of door or inability to open or close it if there should be deformation of door frame from b ground round movement or swelling of the door or frame 5 where there is necessity for very frequent opening of doors controlling main air currents or where such doors must remain open long periods of time it is very advisable to have two or more doors placed so that when one must open one or more may be closed hence prevent loss of air 6 all employees should be educated to respect doors and especially to lo close those which are supposed to be closed it is advisable to have on each door a sign such as keep this door closed or close this door in case of fire in main shaft or other sign applicable to the specific condition existing Z at each door any employee failing to close a door which should be kept closed or one who deliberately or carelessly breaks a door or its frame should be disciplined 7 it is extremely desirable that all mines be divided into air splits by doors etc such that a fire in in any one split will be held separate from all other splits and by manipulation of doors the fire itself isolated and controlled in ordinary times this system operates to the benefit of distribution of air currents to the places where men work |