The propensity for an activated carbon filter to remove organic pollutants from the air of an OR when interfaced with a medical grade air cleaning device was assessed by monitoring the VOC levels in the room with the air recirculating functionality of the device on and off. The room was pre-polluted with toluene, a surgically relevant and common VOC. Figure shows the VOC levels in ppm as a function of time for sensor 1 (18 ft. from the device, near wall on opposite side of room) and sensor 2 (7 ft. from the device, near wall on same side of the room) over a period of 230 min., which approximately matches the upper range of operating times for various surgeries reported in a recent study (mean of 130 ± 97 min.). Data from both sensors show that the concentration of toluene in the air reduces at a much greater rate when the machine is on compared to when it is off. While the door was kept closed and the room contains no open windows, natural loss of toluene is not unexpected as Brownian motion of the toluene gas will predictably find escape routes in the inherent room crevices (ventilation openings, ceilings panels, etc.), however, when air is channeled through the activated carbon filter the VOC levels diminish rapidly. After 130 min., sensor 1 readings show that detected VOC levels are reduced by approximately 25% when the air cleaning device is on. In contrast, the VOC levels are reduced by only 6% when the device is off. Sensor 2 shows similar reductions of 30% when the device is on and less than 1% change when the device is off, indicating that, spatially, the air content change is similar near and far from the position of air recirculation through the activated carbon filter. VOC decays obtained when the device was on were fit with a biexponential decay. For sensor 1, two time constants (t1 and t2) of 69 ±2 and 790 ±40 min. were extracted from the fitting and differ by an order of magnitude. Similarly, for sensor 2, time constants (t1 and t2) of 42 ±2 and 640 ±3 min. were extracted. The biexponential decay implies at least two processes are occurring and could be related to natural loss of VOC in combination with adsorptive capture by the activated carbon, or different adsorption processes with differing rates occurring at the surface of the activated carbon. It's worth noting that dynamics at surfaces have previously been shown to require biexponential fitting to properly model their kinetics. The similarity in the decay profiles for both sensors shows that the use of the activated carbon filter effectively reduces VOCs throughout the OR regardless of vicinity to the air recirculation device. In order to further demonstrate that the activated carbon filter reduces the concentration of toluene in the air, we inserted an activated carbon filter into the device immediately after monitoring VOC levels with the device off. After insertion, the device was immediately turned on. All other room conditions were kept the same. Figure shows how the VOC levels undergo an abrupt and rapid reduction when the device equipped with an activated carbon filter is turned on immediately after monitoring for several hours with the device off. The abrupt and discontinuous change in VOC reduction occurs once the air is forced to flow through the activated carbon filter, showing that differences between the on state and off state cannot simply be explained by natural physical changes such as thermal gradients, humidity levels or changes in barometric pressure. Filters based on surface adsorption lose binding sites over time and become saturated as they adsorb pollutants. Replenishing uncontaminated surface area by inserting a fresh filter is expected to increase the rate of VOC reduction. After 22 h of running the device in the contaminated OR, the used activated carbon filter was removed. Upon insertion of a fresh sheet of activated carbon the rate of VOC reduction showed a clear increase as presented in Figure . This further supports the effectiveness of interfacing activated carbon with the air recirculating device. The use of activated carbon to remove VOCs from the air is a known technology, however, it is often overlooked that the binding strength of VOCs to activated carbon will change with molecular structure and whether or not the surface of the activated carbon was chemically modified. As a result, much of the literature regarding this topic requires careful assessment. Further, the effectiveness of a thin sheet of activated carbon in a specific application requires testing as the size of the room, airflow and physical barriers can affect transport to the surface of the activated carbon film. Further, the strength of surface binding can potentially be affected by the airflow conditions of the device. In an OR environment, devices must conform to applicable regulations, therefore, it is important to test the efficacy of approved equipment. The device used in this study is FDA approved for biomedical applications and is currently used in ORs to maintain clean air. In an OR, toluene and other VOCs are produced as a byproduct of electrosurgery. The commercially available activated carbon used in this study is effective at removing toluene from the OR air as shown by the data in Figures . Note that a sensor 18 ft. from the air cleaning device shows clear reductions in detected VOC levels, demonstrating that VOCs are reduced throughout the room and not just in the local vicinity of the air recirculating device. It is important to highlight that the gas phase toluene was not directed to the device via tubing. Instead, the toluene was allowed to pollute the air as it would in a surgical procedure. The device's own airflow directing capabilities were the only influence on delivering the toluene to the surface of the filter. Given the known propensity of aromatic molecules to interact with pi-saturated surfaces, we expect similar reductions in structurally related VOCs. Note, however, that one cannot simply extrapolate toluene reduction to all VOCs. For example, polar molecules are expected to adsorb less effectively. Additionally, different sources of activated carbon might have different surface functionality and cleanliness. Given the variable structural aspects of activated carbon and devices used to realize its VOC mitigating capabilities, field studies that challenge air cleaning devices under applicable environmental conditions will shed further light on best practices for managing occupational environments exposed to hazardous chemicals.