Casual contact (sharing toilets, drinking glasses, working together, shaking hands, hugging…) with a person living with Hep C, poses no transmission risk.
Hepatitis C is a blood-borne infection, which means that transmission is possible when the blood of someone with Hep C comes into contact with someone else’s blood stream. Prevention measures focus on avoiding shared drug use equipment, un-sterilized tattoo or piercing equipment, and while the risks are lower for transmission it’s also recommended to practice safe sex, prevent needle stick injuries, and avoid sharing household objects that may come in contact with blood, like tooth brushes, nail clippers etc…
Working with someone with Hep C likely means that they pose no risk to you whatsoever. In fact, there are many Canadians who have Hep C and don’t know it, so you may have a few more co-workers with Hep C than you (or they) even know.
CATIE has more information on how Hep C is transmitted, who should get tested, and how to prevent transmission. Your co-worker may not want to discuss their health status with their colleagues, so if you need more information, CATIE is a good place to start.