On May 31, 2005, a 58-year-old male career Fire Fighter (FF) began physical fitness training after, eating lunch. After using the seated rowing machine, he suddenly collapsed. A nearby crew member saw, the collapsed FF and notified crew members in the station and Dispatch, who sent an ambulance and a paramedic unit. Cardiopulmonary resuscitation (CPR) was performed, advanced life support (ALS) treatment was given, and the FF was transported to the local hospital's emergency department (ED). Despite ALS treatment in the ED, the FF died. The death certificate and the autopsy (both completed by the Medical Examiner) listed "calcific sclerosis of the aortic valve with aortic stenosis" as the cause of death, with "atherosclerotic coronary artery disease (CAD)" as a significant condition. The NIOSH investigator concluded that the FF's sudden cardiac death was due to his underlying aortic valve disease and his atherosclerotic CAD, possibly triggered by the physical exertion associated with physical fitness training. NIOSH investigators offer the following recommendations to prevent similar incidents, and to address general safety and health issues: 1. Provide annual medical evaluations to ALL fire fighters to determine their medical ability to perform duties without presenting a significant risk to the safety and health of themselves or others. 2. Provide fire fighters with medical evaluations and clearance to wear self-contained breathing apparatus (SCBA). 3. Phase in a MANDATORY wellness/fitness program for fire fighters to reduce risk factors for cardiovascular disease and improve cardiovascular capacity. 4. Perform an annual physical performance (physical ability) evaluation to ensure fire fighters are physically capable of performing the essential job tasks of structural fire fighting. 5. Discontinue routine annual chest x-rays for hazardous materials technicians unless medically indicated. 6. Discontinue routine drug screens as part of the annual medical evaluation unless for cause.