 The purpose of this single-center, multi-arm, randomized controlled study is to evaluate use of the ISO-Gard mask in patients immediately following a surgical procedure in which inhaled anesthetic is used as the primary modality of anesthesia, for the following: 1 measure the waste anesthetic gas emanating from patient during the immediate one hour post-operative recovery period in the PACU; 2 measure waste anesthetic gas within PACU caregivers breathing zone; and 3 determine the efficacy of the ISO-Gard mask in reducing caregivers exposure to waste anesthetic gas in the PACU. 