92 



THE INDIA RUBBER WORLD 



November 1, 1920 



j)ancl boards and other electrical equipment, and these railings 

 w rapped with friction tape, particularly where workmen operate 

 the electric switch and may be in contact with railing. Pipe rail- 

 ings around pits, such as for motor drives, are often covered 

 with steel plate from floor to top of railing so that materials 

 may be stored adjacently without falling into the pit. 



1. will make the mill room a safe and cheerful place to work. 

 .\n inexpensive lighting unit may be used, the reflector being of 

 metal, dome type, porcelain enameled. This reflector used with 

 a bowl enameled type C lamp of high wattage, will produce a 

 diffused, high intensity, non-glaring illumination. However, 

 where ventilating hoods are placed above the mills it will be 



FiG.4. E.\CH MiLLis Proviued WITH A Sheet Ikon Hood 



A mixing apron is desirable for continuously feeding rubber 

 and pigments into the rolls. This apron reduces the number of 

 manual operations which would otherwise be necessary to feed 

 the mill entirely by hand, and therefore it proportionately re- 

 <!uces the possibilities of injury to the operator. The apron 

 should not be closer than five inches above the mill pan. 

 MISCELLANEOUS SAFEGUARDS AROUND MILLS 



Many injuries have resulted by workmen falling on slippery 

 mill room floors, and various floor coverings such as rubber 

 mats and non-slip metal have been provided for the operator to 

 stand upon. These are not entirely satisfactory except that 

 light weight non-slip metal can be used to good advantage for 

 cross overs between mills to cover the pit and line shaft, and 

 where it is necessary to remove floor for repairs to equipment. 

 A non-slip cement floor can be made perfectly satisfactory and 

 maintain a perfectly smooth surface. Several prominent firms 

 have laid such floors for years by constructing the original floor 

 finish with a carborundum treatment as follows : 



Proceed as in a neat cement floor finish to the point where the 

 area has first been wood floated to a level surface and finished 

 smooth vifith steel floats, then sprinkle the finished area with a 

 dry mixture composed of one part of 12-30 carborundum grit 

 and two parts of Portland cement. Wood float to a smooth sur- 

 fact and finish with steel float. Sprinkle the area a second time, 

 wood float to a smooth surface and again finish with a steel 

 float. In the two sprinklings use one and one-third pounds of 

 carborundum grit to each square yard of surface. Cover and 

 keep wet seven days, or longer, the same as for neat cement 

 finish. 



The above method will make a floor surface which is con- 

 siderably harder than the ordinary cement finish. This method 

 ■can also be used in combination with the metallic floor hardeners. 



Several accidents have been attributed to improper lighting 

 of mill rooms. Momentary blindness of workman caused by ex- 

 cessive glare of lamps may be the cause of a workman making 

 a wrong movement. A poor lighting system will produce fatigue 

 due to continuous eye strain. A general lighting system of uni- 

 formly spaced units distributing light equally over th? whole 

 mill room, with an intensity of 5 foot-candles, as shown in Fig. 



Fig. 5. Mill Pits and Switchboards Should be Safeguarded 



necessary to install a local lamp under the hood in such a loca- 

 tion that it will be up and out of the normal vision. This lamp 

 should be covered with a heavy cage to protect it from breakage. 

 The intensity of light on the mill rolls should be the same as 

 provided in the general lighting system. This is important, for 

 if the light on mill rolls were different from that outside the 

 hood, eye strain would be produced, with resulting discomforts 

 and hazards. 



SAFEGUARDING HEALTH IN MILL ROOM 



Ventilation and cleanliness are equally important with mechani- 

 cal safeguards. It is possible that a workman can operate for a 

 lifetime a machine having not a single safeguard, but not so, if 

 he is compelled to work in a poorly ventilated, dirty room, for 

 he may eventually become as much if not more of a physical 

 wreck as though he had been injured on his machine. Bad 

 ventilation and dry, dusty atmosphere dull the workman, and slow 

 down his productiveness. In mill rooms the installation of a 

 ventilating system is absolutely necessary. Oftentimes natural 

 ventilation may accomplish fairly good results, especially in a 

 small mill room having a high ceiling. However, it is impossible 

 to handle a few pigments, such as lampblack, zincs and leads, as 

 well as soapstone, satisfactorily, without mechanical ventilation. 

 The ideal ventilating system is one which will heat, ventilate, 

 clean and humidify the air. Local conditions and first cost often 

 prevent a near approach to this ideal. Because the maintenance 

 of air washers handling rubber pigments has been difficult, many 

 systems have been installed without the \.ashers, with success. A 

 brief description of such a system is as follows: 



Heat, dust, and fumes arising over the mills are carried away 

 by an exhaust system. Each mill is provided with a sheet iron 

 hood covering the mill. The under side of this hood should 

 not be less than 6 feet 6 inches above the floor upon which the 

 workman stands. Fig. 4 illustrates this hood and the air ducts. 

 The two sides of the hood over the housings are enclosed with 

 sheet iron, but the front and rear are open. However, conditions 

 often demand that canvas curtains on spring rollers be mounted 

 upon the front or rear of the hood to prevent the operator 

 actually throwing compounds across the rolls and out on other 

 side of the mill. Fig. 4-A illustrates a cross-section of the 



