In this factual situation are there any potential causation issues, both cause in fact and proximate cause, that may help us escape potential liability?

The company that you work for operates a small manufacturing plant in Rapid City South Dakota. South Dakota has placed no restraints on it’s citizens in response to the pandemic. Production line employees must work in close physical proximity to other employees. Management has kept the plant open during the current pandemic, justifying this by pointing out that there have had no reported cases of the virus among the employees. No masks or other forms of personal protection equipment have been provided to the workers. Your supervisor has requested that you evaluate the possibility of negligence liability for the company if the plant becomes a hot spot for the transmission of the virus. The boss wants your thoughts on the following questions: How does negligence law determine whether we have a legally imposed duty to protect our employee’s health in this situation ? Do we have such a duty? In this factual situation are there any potential causation issues, both cause in fact and proximate cause, that may help us escape potential liability?