In an action to recover damages for personal injuries sustained by an employee arising out of and in the course of the employee's employment, or for death resulting from such injuries, it is not a defense to an employer, except as hereinafter specified:
1. Employee negligent. That the employee was negligent;
2. Fellow employee negligent. That the injury was caused by the negligence of a fellow employee; or
3. Employee assumed risk. That the employee has assumed the risk of the injury.