Ziqing Zhuang

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A recent study was conducted to compare five fit test methods for screening out poor-fitting N95 filtering-facepiece respirators. Eighteen models of NIOSH-certified, N95 filtering-facepiece respirators were used to assess the fit test methods by using a simulated workplace protection factor (SWPF) test. The purpose of this companion study was to investigate(More)
The objective of this study was to better understand the benefit of the user seal check step for respirator test subjects in the N95 filtering facepiece respirator donning process. To qualify for the study, subjects were required to pass a standard quantitative fit test on at least one of the three N95 filtering facepiece respirator models: 3M 1860 (cup),(More)
The National Institute for Occupational Safety and Health (NIOSH), recognizing the difficulties inherent in using old military data to define modern industrial respirator fit test panels, recently completed a study to develop an anthropometric database of the measurements of heads and faces of civilian respirator users. Based on the data collected, NIOSH(More)
Three fit test methods (Bitrex, saccharin, and TSI PortaCount Plus with the N95-Companion) were evaluated for their ability to identify wearers of respirators that do not provide adequate protection during a simulated workplace test. Thirty models of NIOSH-certified N95 half-facepiece respirators (15 filtering-facepiece models and 15 elastomeric models)(More)
This study aimed to quantify the variability between different anthropometric panels in determining the inward leakage (IL) of N95 filtering facepiece respirators (FFRs) and elastomeric half-mask respirators (EHRs). We enrolled 144 experienced and non-experienced users as subjects in this study. Each subject was assigned five randomly selected FFRs and five(More)
This study assessed the correlation of N95 filtering facepiece respirator (FFR) fit between a Static Advanced Headform (StAH) and 10 human test subjects. Quantitative fit evaluations were performed on test subjects who made three visits to the laboratory. On each visit, one fit evaluation was performed on eight different FFRs of various model/size(More)
Inter-panel variability has never been investigated. The objective of this study was to determine the variability between different anthropometric panels used to determine the inward leakage (IL) of N95 filtering facepiece respirators (FFRs) and elastomeric half-mask respirators (EHRs). A total of 144 subjects, who were both experienced and non-experienced(More)
BACKGROUND Nanoparticle emission assessment technique was developed to semi-quantitatively evaluate nanomaterial exposures and employs a combination of filter based samples and portable real-time particle monitors, including a condensation particle counter (CPC) and an optical particle counter (OPC), to detect nanomaterial releases. This laboratory study(More)