Lighting, Heating and Ventilating Work Places
Industrial hygiene should be concerned about the temperature, humidity, air pressure, light, ventilation, and heating of the work place. The building should be well lighted. If possible natural light should be provided even though the first cost is considerably greater than that of artificial lighting. There will not only be a better grade of work done in natural light and with less eye strain, but the general health of the workmen will be better. If artificial lighting is used it should be electric light, since it produces less impurities and provides a more even light. The light should be evenly distributed and of a proper distance from workmen so that it will not be reflected directly into their eyes. If the occupation takes the worker out of doors then these features can not be controlled, but in this event attention must be given to the clothing of the workman. Sudden changes in the temperature should be avoided as much as possible. Innate is capable of adapting the body to extremes in temperature, but must be given a sufficient amount of time in which to bring about these changes. Men may work in the frigid temperature or in the torrid temperature and if properly clothed and acclimated will suffer no ill effects.
In many industries the laborers are forced to work in artificially high temperatures. Blast-furnace workers, glass blowers, miners, bakers, and stokers must remain in extremely high temperatures. The body may be adapted to such temperature, but the effect of the continued expenditure of energy necessary to bring about this adaptation will show adverse effects upon the body. There is a tendency to respiratory disorders and a thickening of the blood plasma which disrupts the circulatory system. Heat also has a detrimental effect upon the eyes and there is a tendency to rheumatism.
Air of a high relative humidity is objectionable from a hygienic standpoint because it interferes with perspiration and evaporation. Workers constantly exposed to atmosphere that is too damp will have a tendency to incoördinations involving the bodily secretions and respiratory disorders. The ill effects of such an environment are rather marked and if it is necessary to maintain a high relative humidity because of the processes carried on there must be special provision to guard the health of the workers. This may be accomplished by short hours and frequent periods of rest and relief from the high humidity.
Normal air pressure is fifteen pounds to the square inch, but there are many industries in which the work must be done under a greater or a less pressure. Mountain climbers are subjected to decreased air pressure while caisson workers and divers must work under greatly increased air pressure. Decreased air pressure is especially detrimental to those suffering from cardiac disorders, and may in some cases result in death. The effects of increased air pressure have been elaborated upon in another chapter and the student is referred to that section.
The location of the work is important. Subsurface work is more detrimental to health than surface work unless special precautions have been taken to make the place of work conducive to the expression of life. Subsurface workers such as miners are subjected to great heat, lack of proper light and ventilation, accumulated gases, dampness and poisons. There is also greater danger from accidents and explosions.