An Automated Filter Tester Based on an Electrostatic Particle Counter for Testing the Particle Filtration Efficiency of Surgical Masks and N95 Masks
Keywords:
COVID-19, Filter Tester, Filtration Efficiency, Surgical Mask, RespiratorAbstract
The aim of this study is to develop and evaluate an automated filter tester based on an electrostatic counter for determining penetration or filter efficiency and pressure drop of surgical masks and N95 masks. The prototype of the automated filter tester was built based on the TIS 2424-2562 and TIS 2480-2562 standards and experimentally tested. The developed filter tester consisted of an aerosol atomizer, an air heater, a filtered air supply, an aerosol neutralizer, a mixing chamber, a heater, a filter holder, a pressure transducer, a diffusion dryer, an electrostatic particle counter, a mass flow meter and controller and a vacuum pump. In the developed filter tester, PSL and NaCl particles could be generated with number concentration ranging from about 1 to 20,000 particles/cm3. The developed filter tester was designed to operate at a test aerosol flow rate of about 5 to 100 L/min with particle filtration efficiency up to 99.999%. In this study, the particle filtration efficiency from the developed filter tester was compared with that obtained from the light scattering particle counting filter tester and good agreement was found from the comparison, the difference in the filtration efficiency of 0.1 µm PSL particles and 0.264 µm NaCl particles between the developed filter tester and the scattering particle counting filter tester was approximately 0.35% and -0.47%, respectively. It was shown that the developed prototype can be used in the automated filter tester and testing of a prototype of the automated filter tester showed promising results for determining penetration or filtration efficiency of particles and pressure drop of surgical masks and N95 masks.
References
COVID-19 situation report, Department of Disease Control, May. 18, 2021. [Online]. Available: https://covid19.ddc.moph.go.th/
K. O’Dowd, K. M. Nair, P. Forouzandeh, S. Mathew, J. Grant, R. Moran, J. Bartlett, J. Bird and S. C. Pillai, “Face Masks and Respirators in the Fight Against the COVID-19 Pandemic: A Review of Current Materials, Advances and Future Perspectives,” Materials, vol. 13, no. 15, 2020, Art. no. 3363, doi: 10.3390/ma13153363.
N. El-Atab, N. Qaiser, H. Badghaish, S. F. Shaikh and M. M Hussain, “Flexible Nanoporous Template for the Design and Development of Reusable Anti-COVID-19 Hydrophobic Face Masks,” ACS Nano, vol. 14, no. 6, pp. 7659–7665, 2020, doi:10.1021/acsnano.0c03976.
E. E Sickbert-Bennett, J. M. Samet, P. W. Clapp, H. Chen, J. Berntsen, K. L. Zeman, H. Tong, D. J. Weber and W. D. Bennett, “Filtration Efficiency of Hospital Face Mask Alternatives Available for Use During the COVID-19 Pandemic,” JAMA Internal Medicine, vol. 180, no. 12, pp.1607–1612, 2020, doi: 10.1001/jamainternmed.2020.4221.
A. Konda, A. Prakash, G. A. Moss, M. Schmoldt, G. D. Grant and S. Guha, “Aerosol Filtration Efficiency of Common Fabrics Used in Respiratory Cloth Masks,” ACS Nano, vol. 14, no. 5, pp.6339–6347, 2020, doi: 10.1021/acsnano.0c03252.
O. Aydin, B. Emon, S. Cheng, L. Hong, L. P. Chamorro and M. T. A. Saif, “Performance of Fabrics for Home-made Masks Against the Spread of COVID-19 through Droplets: A Quantitative Mechanistic Study,” Extreme Mechanics Letters, vol. 40, 2020, Art. no.100924, doi: 10.1016/ j.eml.2020.100924.
S. Rengasamy, B. Eimer and R. E. Shaffer, “Simple Respiratory Protection—Evaluation of the Filtration Performance of Cloth Masks and Common Fabric Materials Against 20–1000 nm Size Particles,” The Annals of Occupational Hygiene, vol. 54, no. 7, pp.789–798, 2010, doi: 10.1093/annhyg/meq044.
H. Whiley, T. P. Keerthirathne, M. A. Nisar, M. A. F. White and K. E. Ross, “Viral Filtration Efficiency of Fabric Masks Compared with Surgical and N95 Masks,” Pathogens, vol. 9, no. 9, 2020, Art. no. 762, doi: 10.3390/pathogens9090762.
C. M. Dugdale and R. P. Walensky, “Filtration Efficiency, Effectiveness, and Availability of N95 Face Masks for COVID-19 Prevention,” JAMA Intern Medicine, vol. 180, no. 12, pp.1612–1613, 2020, doi: 10.1001/jamainternmed.2020.4218.
P. Intra, “Filtration Efficiency of Surgical Masks, Fabric Masks and N95/KN95/FFP1/FFP2 Masks Available for Use during the COVID-19 Pandemic in Thailand,” Thai Science and Technology Journal (TSTJ), vol.29, no.5, pp.904–918, 2021.
Automated Filter Tester Model 8130A, TSI Inc., Jan. 12, 2022. [Online]. Available: https://tsi.com/products/filter-testers/automated-filter-tester-8130a/
Automated Filter Tester Model 3160, TSI Inc., Jan. 12, 2022. [Online]. Available: https://tsi.com/ products/filter-testers/automated-filter-tester-3160/
G506 Mask Automatic Filter Performance Tester, Qinsun Instruments Co., Ltd., Jan. 12, 2022. [Online]. Available: http://www.testerinlab.com/products/Others/2018/0316/200.html
42 CFR Part 84 Respiratory Protective Devices, National Institute for Occupational Safety and Health , Mar. 4, 1997. [Online]. Available: https://www.cdc.gov/niosh/npptl/topics/respirators/pt84abs2.html
Standard Test Method for Determining the Initial Efficiency of Materials Used in Medical Face Masks to Penetration by Particulates Using Latex Spheres, ASTM F2299/F2299M-03(2017), ASTM International, West Conshohocken, PA. USA, 2017.
Standard Specification for Performance of Materials Used in Medical Face Masks, ASTM F2100-19e1, ASTM International, West Conshohocken, PA, USA, 2019.
B. Y. H. Liu and D. Y. H. Pui, “Equilibrium bipolar charge distribution of aerosols,” Journal of Colloid and Interface Science, vol.49, no.2, pp.305–312, 1974, doi:10.1016/0021-9797(74)90366-X.
P. Intra and N. Tippayawong, “Performance evaluation of an electrometer system for ion and aerosol charge measurements,” Korean Journal of Chemical Engineering, vol.28, no.2, pp.527–530, 2011, doi: 10.1007/s11814-010-0378-1.
P. Intra, A. Yawootti and N. Tippayawong, “An electrostatic sensor for continuous monitoring of particulate air pollution,” Korean Journal of Chemical Engineering, vol. 30, no. 12, pp. 2205–2212, 2013, doi: 10.1007/s11814-013-0168-7.
P. Intra and N. Tippayawong, “Development and evaluation of a Faraday cup electrometer for measuring and sampling atmospheric ions and charged aerosols,” Particulate Science and Technology, vol. 33, no. 3, pp. 257–263, 2015, doi:10.1080/02726351.2014.952392.
P. Intra, V. Asanavijit and W. Rattanachan, “Evaluation of the Particle Filtration Efficiency of Surgical Masks by Electrostatic and Light Scattering Particle Counters,” Ladkrabang Engineering Journal, vol.39, no. 2, pp. 53–69, 2022.
K. Willeke and P. A. Baron, “Filter collection,” in Aerosol Measurement: Prnciples, Techniques, and Applications, New York, USA: John Wiley & Sons, 1993, ch. 10, pp. 179–205.
P. Intra, and N. Tippayawong, “Experimental characterization of a short electrical mobility spectrometer for aerosol size classification,” Korean Journal of Chemical Engineering, vol. 26, no. 6, pp. 1770–1777, 2009, doi: 10.1007/s11814-009-0261-0.
P. Intra, and N. Tippayawong, “Development of a fast-response, high-resolution electrical mobility spectrometer,” Korean Journal of Chemical Engineering, vol. 28, no. 1, pp. 279–286, 2011, doi: 10.1007/s11814-010-0326-0.
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