The turn of the 20th century was marked by growth in communication, mechanization, science and transportation that supported American industrial expansion. Scientists and industrialists worked together to develop inventions harnessing the power of electricity and expanding current machining capabilities. While corporate leaders capitalized on industrial and technological growth, working men, women and children were subject to harsh conditions inside factories.

Dangerous Machines

The machines that made mass manufacturing possible were often very dangerous. Kept in small spaces without proper enclosure or ventilation, manufacturing machines emitted noxious fumes and contributed to excessive heat inside factories filled with workers. The exposed machinery routinely claimed lives and maimed laborers. In 1900, 35,000 workers were killed in industrial accidents, according to the ''Gale Encyclopedia of U.S. Economic History.'' That same year, 500,000 were maimed in factory accidents.

Long Hours

Work in the factories was long and monotonous. The average worker completed the same task, over and over, for at least 10 hours a day. Working long hours, six days per week contributed to extreme fatigue, illness and even injury. Children often worked even longer hours -- those who lived at the factory worked up to 18 hours a day.

Low Pay

The mechanization of the industrial age allowed businesses to replace skilled laborers in favor of unskilled workers for much less pay. Paired with machines, large groups of unskilled workers were assigned to complete small portions of the manufacturing process. By assigning repetitive tasks to large groups, factories "deskilled" work and lowered wages. Though pay varied by gender and age, typical employees made about $6 a week, notes the American Postal Workers Union. This pay, at less than a living wage, forced workers into an endless cycle of poverty.

Child Workers

As factories grew, the demand for cheap labor grew with it. In the late 19th century, many children were drawn into the labor force for work inside factories. With adult wages so low, children were often forced to work in the factories to support their families. In 1900, there were 1.7 million children under the age of 15 working in America, according to the National Archives. Children working in the factories often had spine curvature, stunted growth and contagious diseases like tuberculosis.