180413-N-KF478-533 CORPUS CHRISTI, Texas (April 13, 2018) Erica Magana, left, instructs Hospital Corpsman 3rd Class Federico Cara to inhale as much air as possible during a simulated lung function screening. Magana and Cara are occupational health technicians from Naval Branch Health Clinic Kingsville and Naval Health Clinic Corpus Christi, and are undergoing a one day Spirometry recertification class. (U.S. Navy photo by William Love/Released)