Date of Graduation


Document Type


Degree Type



Statler College of Engineering and Mineral Resources


Industrial and Managements Systems Engineering

Committee Chair

Xinjian He

Committee Co-Chair

Steven Guffey

Committee Member

Steven Guffey

Committee Member

Ziqing Zhuang


Powered air purifying respirators (PAPRs) are commonly used in a health care setting, providing a higher level of protection than traditional surgical masks or N-95’s. However, little can be found in literature about their use in a sterile environment, such as an operating room. Thus, this study aims to compare bacterial contamination of three different models of PAPRs (3MTM VersafloTM TR-600-ECK, 3MTM Air-MateTM, and MAXAIR CAPR 710) to a N-95, surgical N-95 and surgical mask. The experiments were conducted in a small room with no ventilation, under two conditions, door open and door closed. Each experiment was replicated five times per condition, for a total of ten replications per respirator and surgical mask. Data was collected using a colony forming unit (CFU) count from agar plates placed in the testing room. Results showed that all respirators and the surgical mask resulted in a contamination compared to an empty room, but showed significantly less contamination compared to an unprotected subject. All respirators tested generated a lower mean CFU than the surgical mask, and all the PAPRs tested showed less CFU than the surgical N-95. The MAXAIR and Air-Mate were concluded to not differ in mean CFU compared to the N-95, while the Versaflo showed a significant difference in mean CFU. It can be said the Air-Mate and MAXAIR may have the same contamination potential as a N-95, while the Versaflo showed the highest CFU out of all the PAPRs and most likely is not suited for use in a sterile environment.