Sudden cardiac arrest continues to be a major cause of firefighter deaths during training due to a lack of individual firefighter adherence to National Fire Protection Association (NFPA) standards. These standards identify requirements for fire departments to create and maintain fitness programs. Existing research has not identified any relationships between training fatalities and individual firefighter adherence to NFPA 1583, Standard on Health-Related Fitness Programs for Fire Department Members. Using self-determination theory as the foundation, the purpose of this cross-sectional correlation study was to investigate whether individual firefighter adherence to NFPA 1583 has a measurable effect on training fatalities. Survey data were collected from 441 paid firefighters from 7 fire departments located in a rural county in a southern U.S. state. Data were analyzed using multiple linear regression. Results indicated that adherence to NFPA 1583 has a statistically significant relationship with reduced firefighter training fatalities (p = .000). Recommendations include examining adherence policies to all elements of the NFPA 1583 standard, not just chapters 5 through 8 in the publication. These include chapter 1 administration, chapter 2 referenced publications, chapter 3 definitions, and chapter 4 program organization specifications. The study results may be used by fire department training divisions to improve the health and safety of firefighters.