Which of the following are considered the four primary routes of chemical exposure?

The four primary routes of chemical exposure include inhalation, ingestion, skin contact, and injection. Inhalation is the most significant route as it allows chemicals to enter the body quickly through the respiratory system. Ingestion refers to the intake of chemicals through the mouth, which can occur through contaminated food or drink. Skin contact is another critical route, as many chemicals can permeate the skin and enter the bloodstream. Injection is considered an important route as well, particularly for substances that can compromise safety through needles or other penetrating objects.

Understanding these routes is essential for hazmat operators as it enables them to recognize risks and implement appropriate safety measures when dealing with hazardous materials. Other options presented do not accurately reflect the commonly recognized routes of chemical exposure, which can lead to confusion about how to respond effectively to incidents involving hazardous substances.