Whether the product is photographic film, insecticides, prescription medications, or food, it almost certainly contains one of the 50,000 different chemical substances generated by chemical industry personnel. Chemical plant and systems operators control the entire manufacturing process from a control booth, using gauges and computer readouts. 

They ensure that chemicals are mixed in the proper ratios and that reaction speeds, temperatures, and a variety of other variables are within acceptable limits. However, this is not as common as it appears. Chemistry is a science, yet it is still an art on a large scale. Chemical plant and systems operators, like all artists, must understand their materials and how they will behave under diverse conditions. 

After all, not every batch of raw materials is uniformly pure, and moisture content varies depending on the weather. Any chemical process can be influenced by these and dozens of other factors. Computers can be useful. In the end, however, it is the expertise, talent, and seasoned judgement of chemical plant and systems operators that ensure uniform product quality.