Final answer:
The Occupational Safety and Health Administration (OSHA) requires medical offices to maintain a written emergency evacuation plan as part of their emergency action plan for workplace safety.
Step-by-step explanation:
The federal agency that requires medical offices to maintain a written emergency evacuation plan is OSHA, the Occupational Safety and Health Administration. According to OSHA's guidelines, employers including medical offices must have an emergency action plan that includes procedures for reporting a fire or other emergencies, evacuation procedures and emergency escape route assignments. It is vital for the safety of both employees and patients that these plans are detailed, well understood by all staff members, and practiced regularly.