Cross-contamination prevention systems and cross-contamination prevention methods are provided for defining and automatically enforcing access restrictions between environments where cross-contamination may occur. The system and methods can evaluate a person's exposure to contaminants in one or more locations against contamination risk posed for another location. The system can prevent or allow access to the other location based on that evaluation. Some embodiments can be implemented in a laboratory setting and configured to prevent cross-contamination between different laboratories and/or experiments being conducted.