RecruitingClinical trialLung and Heart Function Across Decades of Life in HealthThe main objective of this study is to develop baseline "normal" reference values of both lung and heart function for healthy adults within the age range relevant to the United States Veteran population who served in the Southwest Asia theater of military operations. This study will involve performing key components of the Department of Veterans Affairs the Airborne Hazards and Open Burn Pit Center of Excellence (AHOBPCE) and a VA network of Post-Deployment Cardiopulmonary Evaluation Network (PDCEN) Core Clinical Evaluation in asymptomatic unexposed healthy controls without known lung or heart disease to serve as a "normal" control comparator group for veterans evaluated by PDCEN.