The study population will consist of 100 subjects between the ages of 18-50 classified as ASA 1 or 2 with no limitations as to gender or race that are scheduled for elective surgery at Cedars-Sinai Medical Center. There are changes to lung functioning as functional residual capacity (FRC), closing capacity, and lung volume after age 50; therefore, the age limitation is set to age 50. Changes in lung and chest wall compliance necessitate the exclusion of anyone over the age of 50. Minors are also excluded as there is difficulty fitting the face mask due to a smaller physiology.