Evaluation of Respiratory Rate Readings from later subjects (at least 10) will be used to evaluate the accuracy and validity of respiratory rate measurements extracted from the plethysmogram that was recorded with the Camera Oximeter. Paired respiratory rate readings from the test oximeter and the reference capnometry are grouped into three ranges (0-8, 9-16, and >17 breaths per minute). Mean bias, precision and accuracy are calculated for each group of respiratory range and the overall range.