Assessment of the Qualitative Fit Test and Quantitative Single-Pass Filtration Efficiency of Disposable N95 Masks Following Gamma Irradiation

Cramer, Avilash; Tian, Enze; Galanek, Mitchell; Lamere, Edward; Li, Ju; Gupta, Rajiv; Short, M.J.

doi:10.1001/jamanetworkopen.2020.9961

Cited by 26 publications

(34 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reduction in FE is more for higher flow rate/face velocity. The similar observation also made by other researchers (Amit et al, 2020 and Cramer et al, 2020). The FE is more for 20 lpm than 90 lpm in all the sterilization conditions.…”

Section: Resultssupporting

confidence: 90%

See 1 more Smart Citation

Evaluation of filtration efficacy of various types of facemasks using ambient and PAO aerosols following with different sterilization methods

Kumar

Bhattacharjee²,

Sangeetha

et al. 2020

Preprint

View full text Add to dashboard Cite

Due to the ongoing pandemic, various types of facemasks such as N-95, surgical mask and cloth masks are being used as an essential protective measure. The filtration efficiency of these masks were tested before and after sterilization by different methods for two flow rates conditions corresponding to normal breathe rate (20 lpm) and during sneezing (90 lpm). Sterilization techniques used here are autoclaving (30 and 60 minutes), dry oven heating (30 and 60 minutes), gamma irradiation (15 and 25 kGy), hot water washing with and without detergent and immersing in 10% concentration of liquid hydrogen peroxide for 30 minutes. As expected, the N-95 is the greatest filtering efficiency among all the other type face masks. The best method to sterilize N-95 masks without affecting its performance is by using dry heat with temperature ranging from 70-80oC. The cloth masks and surgical mask are performed more or less same for both flow conditions. As an affordable sterilization method hot water washing is highly recommended which does not deteriorate the efficiency of the masks and can be used for the general public. The use of double or triple layer cotton cloth masks in the general public serves fit for the purpose than surgical masks. The surgical mask can be sterilized only few times with the help of dry heat, hot water wash and/or autoclave.

show abstract

Section: Resultssupporting

confidence: 90%

“…Under these scenario, multiple potential methods for sterilization have begun to be explored (Juan et al, 2020).The thermal heat, radiation or chemical agents usually do this. disadvantages from one than others (Cramer et. al., 2020;Juan et al, 2020).…”

Section: Introductionmentioning

confidence: 99%

Evaluation of filtration efficacy of various types of facemasks using ambient and PAO aerosols following with different sterilization methods

Kumar

Bhattacharjee²,

Sangeetha

et al. 2020

Preprint

View full text Add to dashboard Cite

show abstract

“…Much of the work to date has focused on sterilization of respirators for subsequent reuse. While a few studies have been completed and submitted to preprint servers after waiting for data from extant labs [24][25][26][27][28][29], a number of other preprints [30,31] and publications [32][33][34] have developed apparatuses to measure filtration efficiency as best they can independently. There is significant heterogeneity in these setups; some are built with assistance from labs which study aerosols, others with equipment found on hand.…”

Section: Introductionmentioning

confidence: 99%

Measurement of filtration efficiencies of healthcare and consumer materials using modified respirator fit tester setup

et al. 2020

View full text Add to dashboard Cite

During the current SARS-CoV-2 pandemic there is unprecedented demand for personal protective equipment (PPE), especially N95 respirators and surgical masks. The ability of SARS-CoV-2 to be transmitted via respiratory droplets from asymptomatic individuals has necessitated increased usage of both N95 respirators in the healthcare setting and masks (both surgical and homemade) in public spaces. These precautions rely on two fundamental principles of transmission prevention: particle filtration and droplet containment. The former is the focus of NIOSH N95 testing guidelines, and the latter is an FDA guideline for respirators and surgical masks. While studies have investigated droplet containment to provide guidance for homemade mask production, limited work has been done to characterize the filtration efficiency (FE) of materials used in home mask making. In this work, we demonstrate the low-cost (<$300) conversion of standard equipment used to fittest respirators in hospital and industrial settings into a setup that measures quantitative FEs of materials based on NIOSH N95 guidelines, and subsequently measure FEs of materials found in healthcare and consumer spaces. These materials demonstrate significant variability in filtration characteristics, even for visually similar materials. We demonstrate a FE of 96.49% and pressure drop of 25.4 mmH 2 0 for a double-layer of sterilization wrap used in surgical suites and a FE of 90.37% for a combination of consumer-grade materials. The excellent filtration characteristics of the former demonstrate potential utility for emergent situations when N95 respirators are not available, while those of the latter demonstrate that a high FE can be achieved using publicly available materials.

show abstract

“…Instead of sodium chloride (NaCl) aerosols, which are the NIOSH standard, tests performed in this analysis used ambient air as the source for particles of diverse sizes. This test allows an estimation of the FE of the masks[ 29 ].…”

Section: Methodsmentioning

confidence: 99%

Máscaras do Bem: An analysis of face-mask performance from a volunteer mask-making initiative in Ribeirão Preto, Brazil

Leite

Cheng

Kumar

et al. 2021

Public Health in Practice

View full text Add to dashboard Cite

Objectives : This study examines the response of a group of volunteers in Ribeirão Preto, Brazil, as the city faced an unprecedented demand for face masks during the onset of the COVID-19 crisis in 2020. The performance of artisanal-produced masks was compared with industry equivalents. Study design Case report with comparative testing. Methods A comparison was made between two parallel projects that produced single-use masks for healthcare workers and reusable masks for the community. Mask samples were tested for filtration efficiency (FE) and breathability (pressure drop). Results Results for FE averaged 40–60% for healthcare masks and 10% for community masks; both types of masks were tested for particle sizes of 0.3μm. Conclusions While performance was inferior to standard comparators, the masks investigated in this study afforded a level of protection in the absence of alternatives, especially in non-aerosol generating contexts. The findings of this study are useful for communities with limited resources in other developing countries. In addition, insights can be gained from the experiences in Ribeirão Preto in terms of how to respond to future health emergencies.

show abstract

Assessment of the Qualitative Fit Test and Quantitative Single-Pass Filtration Efficiency of Disposable N95 Masks Following Gamma Irradiation

Cited by 26 publications

References 7 publications

Evaluation of filtration efficacy of various types of facemasks using ambient and PAO aerosols following with different sterilization methods

Evaluation of filtration efficacy of various types of facemasks using ambient and PAO aerosols following with different sterilization methods

Measurement of filtration efficiencies of healthcare and consumer materials using modified respirator fit tester setup

Máscaras do Bem: An analysis of face-mask performance from a volunteer mask-making initiative in Ribeirão Preto, Brazil

Contact Info

Product

Resources

About