COMPANIES TAKE THE INITIATIVE ON MINE LIGHTING.

Initial action has been taken by coal mine management to install experimental lighting systems to determine the most advantageous system with which to equip their mining machines. Many companies have installed lighting systems on underground machines to test them under actual conditions, while other firms have decided to install elaborate ″black rooms″ on the surface to check the lighting fixtures under simulated conditions. Simulation of underground conditions includes use of actual machines, with the ″black rooms″ designed with movable roof and ribs to determine the lighting's effectiveness under a range of seam heights and entry widths. The cost of these lighting systems is also examined.