Ronald E. Shaffer

National Institute for Occupational Safety and Health

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

Edward M. Fisher

National Institute for Occupational Safety and Health

Ziqing Zhuang

Taipei Veterans General Hospital

Michael Bergman

National Institute for Occupational Safety and Health

Susan L. Rose‐Pehrsson

United States Naval Research Laboratory

Raymond J. Roberge

Medical Protective

Samy Rengasamy

National Institute for Occupational Safety and Health

Dennis J. Viscusi

National Institute for Occupational Safety and Health

Benjamin C. Eimer

Applied Technical Services (United States)

Andrew J. Palmiero

National Institute for Occupational Safety and Health

Brian K. Heimbuch

Panama Canal Authority

Cooperative Institutions

National Institute for Occupational Safety and Health

139

Centers for Disease Control and Prevention

National Institute of Standards and Technology

West Virginia University

United States Naval Research Laboratory

Institute of Nanotechnology

Glenn Research Center

United States Department of Health and Human Services

Johns Hopkins University

Naval Research Laboratory Chemistry Division

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Impact of Low Filter Resistances on Subjective and Physiological Responses to Filtering Facepiece Respirators

PLoS ONE (2013)

Raymond J. Roberge Jung‐Hyun Kim Jeffrey B. Powell Ronald E. Shaffer Caroline M. Ylitalo

Ten subjects underwent treadmill exercise at 5.6 km/h over one hour while wearing each of three identical appearing, cup-shaped, prototype filtering facepiece respirators that differed only in their filter resistances (3 mm, 6 mm, and 9 mm H2O pressure drop). There were no statistically significant differences between filtering facepiece respirators with respect to impact on physiological parameters (i.e., heart rate, respiratory rate, oxygen saturation, transcutaneous carbon dioxide levels, tympanic membrane temperature), pulmonary function variables (i.e., tidal volume, respiratory rate, volume of carbon dioxide production, oxygen consumption, or ventilation), and subjective ratings (i.e., exertion, thermal comfort, inspiratory effort, expiratory effort and overall breathing comfort). The nominal filter resistances of the prototype filtering facepiece respirators correspond to airflow resistances ranging from 2.1 - 6.6 mm H2O/L/s which are less than, or minimally equivalent to, previously reported values for the normal threshold for detection of inspiratory breathing resistance (6 - 7.6 mm H2O/L/sec). Therefore, filtering facepiece respirators with filter resistances at, or below, this level may not impact the wearer differently physiologically or subjectively from those with filter resistances only slightly above this threshold at low-moderate work rates over one hour.

Respirator

Respiratory Rate

Respiratory minute volume

Treadmill

10.1371/journal.pone.0084901

Cite

Citations (50)

<title>Internal standardization and calibration of surface acoustic wave chemical sensor systems</title>

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE (1999)

Ronald E. Shaffer Michael T. Cygan Sean J. Hart Russell Chung Viet Nguyen

Prototype surface acoustic wave chemical sensor systems are described, which can detect and identify toxic vapors in real-time at trace concentrations. To operate autonomously for long periods, without failure, requires a thorough understanding of the hardware and software requirements of the sensor system. The SAWCAD and SAWRHINO prototypes, which implement several improvements to the hardware, over previously developed systems, are described. Software for vapor detection and neural network identification are also discussed. Preliminary results from two new software enhancements are described. Improved chemical discrimination occurs when the response slopes are incorporated into the analysis of the SAW ambient data. The generalized rank annihilation method is shown to be a powerful tool for extracting pure component analyte signatures from trap and purge gas solid chromatographic SAW data.

TRACE (psycholinguistics)

Chemical sensor

10.1117/12.341034

Cite

Citations (0)

Personal Interventions for Reducing Exposure and Risk for Outdoor Air Pollution: An Official American Thoracic Society Workshop Report

Annals of the American Thoracic Society (2021)

Robert Laumbach Kevin Cromar Gary Adamkiewicz Christopher Carlsten D. Charpin

Section:ChooseTop of pageAbstract <

Personal Protective Equipment

10.1513/annalsats.202104-421st

Cite

Citations (29)

Evaluation of Nano- and Submicron Particle Penetration through Ten Nonwoven Fabrics Using a Wind-Driven Approach

Journal of Occupational and Environmental Hygiene (2010)

Pengfei Gao Peter A. Jaques Ta-Chih Hsiao Angie Shepherd Benjamin C. Eimer

Existing face mask and respirator test methods draw particles through materials under vacuum to measure particle penetration. However, these filtration-based methods may not simulate conditions under which protective clothing operates in the workplace, where airborne particles are primarily driven by wind and other factors instead of being limited to a downstream vacuum. This study was focused on the design and characterization of a method simulating typical wind-driven conditions for evaluating the performance of materials used in the construction of protective clothing. Ten nonwoven fabrics were selected, and physical properties including fiber diameter, fabric thickness, air permeability, porosity, pore volume, and pore size were determined. Each fabric was sealed flat across the wide opening of a cone-shaped penetration cell that was then housed in a recirculation aerosol wind tunnel. The flow rate naturally driven by wind through the fabric was measured, and the sampling flow rate of the Scanning Mobility Particle Sizer used to measure the downstream particle size distribution and concentrations was then adjusted to minimize filtration effects. Particle penetration levels were measured under different face velocities by the wind-driven method and compared with a filtration-based method using the TSI 3160 automated filter tester. The experimental results show that particle penetration increased with increasing face velocity, and penetration also increased with increasing particle size up to about 300 to 500 nm. Penetrations measured by the wind-driven method were lower than those obtained with the filtration method for most of the fabrics selected, and the relative penetration performances of the fabrics were very different due to the vastly different pore structures.

Penetration (warfare)

10.1080/15459624.2010.515554

Cite

Citations (34)

The Application of Chemometric Methods to Correlate Fuel Performance with Composition from Gas Chromatography

Energy & Fuels (2004)

Robert E. Morris Mark H. Hammond Ronald E. Shaffer W. Payton Gardner Susan L. Rose‐Pehrsson

A group of JP-5 fuels, which had passed all specification testing, were causing catastrophic turbine engine failures. Laboratory examinations of these fuels did not reveal any obvious compositional differences responsible for the unacceptable performance. Since fuel screening with full scale combustor tests are expensive and time-consuming, we investigated the use of chemometric analysis to predict fuel suitability from capillary gas chromatography. From a small group of acceptable and problem fuels, a correlation model was developed that successfully predicted fuel suitability, as long as the overall composition of the fuels was similar. To increase sensitivity and allow correlations of minor compositional changes, data preprocessing methods were developed to minimize instrumental errors and to focus the analysis on subtle compositional differences that were responsible for the unacceptable combustion performance.

10.1021/ef030131w

Cite

Citations (8)

Prevalence of Respiratory Protective Devices in U.S. Health Care Facilities

Workplace Health & Safety (2016)

Kerri Wizner Lindsay R. Stradtman Debra Novak Ronald E. Shaffer

An online questionnaire was developed to explore respiratory protective device (RPD) prevalence in U.S. health care facilities. The survey was distributed to professional nursing society members in 2014 and again in 2015 receiving 322 and 232 participant responses, respectively. The purpose of this study was to explore if the emergency preparedness climate associated with Ebola virus disease changed the landscape of RPD use and awareness. Comparing response percentages from the two sampling time frames using bivariate analysis, no significant changes were found in types of RPDs used in health care settings. N95 filtering facepiece respirators continue to be the most prevalent RPD used in health care facilities, but powered air-purifying respirators are also popular, with regional use highest in the West and Midwest. Understanding RPD use prevalence could ensure that health care workers receive appropriate device trainings as well as improve supply matching for emergency RPD stockpiling.

Respirator

Preparedness

Personal Protective Equipment

10.1177/2165079916657108

Cite

Citations (59)

Analysis of Multi-Criteria Fire Detection Data and Early Warning Fire Detection Prototype Selection

Susan L. Rose‐Pehrsson Sean J. Hart Ronald E. Shaffer Daniel T. Gottuk Jennifer T. Wong

Abstract : This report describes the analysis of Fire/Nuisance Source data and the selection of sensors for an early warning, multi-criteria, fire detection system for the Office of Naval Research (ONR) program on Damage Control: Automation for Reduced Manning (DC-ARM). In this work, the analysis of transient fire signatures is studied using a probabilistic neural network (PNN). Experiments are described to study the effects of various PNN training parameters and to determine the optimal sensor suite combination, which enables both early fire detection and high nuisance source rejection. Comparisons are made between the candidate sensor arrays, commercial fire detection systems, and sensor arrays proposed in previous reports Recommendations and directions for future research are also given.

Fire Detection

Transient (computer programming)

Source

Cite

Citations (3)

Resistance to synthetic blood penetration of National Institute for Occupational Safety and Health-approved N95 filtering facepiece respirators and surgical N95 respirators

American Journal of Infection Control (2015)

Samy Rengasamy Deborah Sbarra Julian Nwoko Ronald E. Shaffer

•We measure the resistance to blood penetration for NIOSH-approved N95 respirators.•Several N95 models show resistance to penetration using the ASTM F1862 test method.•Resistance decreases with increasing velocity.•Respirator filter media composition influences blood penetration. BackgroundSurgical N95 filtering facepiece respirators (FFRs), certified by the National Institute for Occupational Safety and Health (NIOSH) as a respirator and cleared by the Food and Drug Administration (FDA) as a surgical mask, are often used to protect from the inhalation of infectious aerosols and from splashes/sprays of body fluids in health care facilities. A shortage of respirators can be expected during a pandemic. The availability of surgical N95 FFRs can potentially be increased by incorporating FDA clearance requirements in the NIOSH respirator approval process.MethodsFluid resistance of NIOSH-approved N95 FFRs, and FDA-cleared surgical N95 FFRs and surgical masks was tested using the ASTM F1862 method at 450 and 635 cm/sec velocities and compared with the results from a third-party independent laboratory. Blood penetration through different layers of filter media of masks were also analyzed visually.ResultsFour N95 FFR models showed no test failures at both velocities. The penetration results obtained in the NIOSH laboratory were comparable to those from the third-party independent laboratory. The number of respirator samples failing the test increased with increasing test velocity.ConclusionsThe results indicate that several NIOSH-approved N95 FFR models would likely pass FDA clearance requirements for resistance to synthetic blood penetration. Surgical N95 filtering facepiece respirators (FFRs), certified by the National Institute for Occupational Safety and Health (NIOSH) as a respirator and cleared by the Food and Drug Administration (FDA) as a surgical mask, are often used to protect from the inhalation of infectious aerosols and from splashes/sprays of body fluids in health care facilities. A shortage of respirators can be expected during a pandemic. The availability of surgical N95 FFRs can potentially be increased by incorporating FDA clearance requirements in the NIOSH respirator approval process. Fluid resistance of NIOSH-approved N95 FFRs, and FDA-cleared surgical N95 FFRs and surgical masks was tested using the ASTM F1862 method at 450 and 635 cm/sec velocities and compared with the results from a third-party independent laboratory. Blood penetration through different layers of filter media of masks were also analyzed visually. Four N95 FFR models showed no test failures at both velocities. The penetration results obtained in the NIOSH laboratory were comparable to those from the third-party independent laboratory. The number of respirator samples failing the test increased with increasing test velocity. The results indicate that several NIOSH-approved N95 FFR models would likely pass FDA clearance requirements for resistance to synthetic blood penetration.

Respirator

2019-20 coronavirus outbreak

10.1016/j.ajic.2015.06.014

Cite

Citations (16)

Assessing the efficacy of tabs on filtering facepiece respirator straps to increase proper doffing techniques while reducing contact transmission of pathogens

Journal of Occupational and Environmental Hygiene (2016)

Amanda Strauch Tyler Brady George Niezgoda Claudia M. Almaguer Ronald E. Shaffer

NIOSH-certified N95 filtering facepiece respirators (FFRs) are used in healthcare settings as a control measure to mitigate exposures to airborne infectious particles. When the outer surface of an FFR becomes contaminated, it presents a contact transmission risk to the wearer. The Centers for Disease Control and Prevention (CDC) guidance recommends that healthcare workers (HCWs) doff FFRs by grasping the straps at the back of the head to avoid contact with the potentially contaminated surface. Adherence to proper doffing technique is reportedly low due to numerous factors including difficulty in locating and grasping the straps. This study compares the impact of tabs placed on FFR straps to controls (without tabs) on proper doffing, ease of use and comfort, and reduction of transfer of contamination to the wearer. Utilizing a fluorescent agent as a tracer to track contamination from FFRs to hand and head areas of 20 human subjects demonstrated that there was no difference in tabbed FFR straps and controls with respect to promoting proper doffing (p = 0.48), but did make doffing easier (p = 0.04) as indicated by 7 of 8 subjects that used the tabs. Seven of the 20 subjects felt that FFRs with tabs were easier to remove, while only 2 of 20 indicated that FFRs without tabs were easier to remove. Discomfort was not a factor for either FFR strap type. When removing an FFR with contaminated hands, the use of the tabs significantly reduced the amount of tracer transfer compared to straps without tabs (p = 0.012). FFRs with tabs on the straps are associated with ease of doffing and significantly less transfer of the fluorescent tracer.

Respirator

Personal Protective Equipment

10.1080/15459624.2016.1179386

Cite

Citations (9)

Development of an Early Warning Multi-criteria Fire Detection System: Analysis of Transient Fire Signatures Using a Probabilistic Neural Network.

Ronald E. Shaffer Susan L. Rose‐Pehrsson Frederick W. Williams Colin M. Barry Daniel T. Gottuk

Abstract : This report describes the progress made in developing an early warning, multi-criteria, fire detection system for the Office of Naval Research (ONR) program on Damage Control: Automation for Reduced Manning (DC-ARM). In this work, the analysis of transient fire signatures is studied using a probabilistic neural network (PNN). Experiments are described to study the effects of various PNN training parameters and to determine the optimal sensor suite combination, which enables both early fire detection and high nuisance source rejection. Comparisons are made between the candidate sensor arrays, commercial fire detection systems, and sensor arrays proposed in previous reports. Recommendations and directions for future research are also given.

Fire Detection

Transient (computer programming)

Source

Cite

Citations (14)