Electrosurgery was performed with an electrical surgery generator (Force EZ) from Valleylab TM set at 60 W power in "cut mode". A sample of porcine muscle was placed on a Valleylab TM Polyhesive TM adult patient return electrode (Covidien, Minneapolis, MN). The electrode was then plugged into the electrosurgery unit. A diathermy tip was attached to the electrosurgery unit and after powering up the device, cuts were made in the porcine muscle until the detected formaldehyde levels reached a sufficiently high level. The room ventilation and positive pressure were turned off. The air recirculating device was on while cuts were made but without catalyst and activated carbon. Once the formaldehyde levels in the room increased by approximately 2.38 ppm, no further cuts were made. Formaldehyde levels were then monitored under three different conditions and compared: 1) without activated carbon and without catalyst; 2) with activated carbon and without catalyst; 3) with activated carbon and with catalyst.