Innovative Team Discovers N95 Masks Can Be Recharged to Restore Their Efficacy
Since the coronavirus crisis was declared a pandemic, N95 masks, which are a design of personal protective equipment have been in short supply.
N95 masks as well as other masks used in the medical field use two filtration methods, electrostatic filtering and mechanical filtering using mask fibers. Electrostatic filtering uses stationary electric charges to attract and catch minute 0.3-micron particles such as fluid droplets that may contain viruses. N95 masks are also only for single day use as they become less effective at filtering out minute particles once the electrostatic charges that are present in the mask leak into the air.
Additionally, high humidity areas speed up the loss of efficiency of N95 masks. Other procedures, such as boiling or baking to decontaminate the masks or using fumigation machines or UV light towers also remove the masks’ electrostatic charge.
However, in a paper that was recently published in the Physics of Fluids journal, turns out you can recharge your N95 mask. Shankar Ghosh and his colleagues from the Tata Institute of Fundamental Research in Mumbai, India, and Dov Levine, discovered that decontaminated N95 masks can be recharged with a jolt of electricity, which restores the masks’ electrostatic charges.
Dov Levine, who is a physicist at Technion-IIT located in Haifa, Israel and the team also created a battery-powered, smart mask prototype that has a removable filter which can be charged continuously in order to maintain high filtration levels even after it’s been in use for hours.
To do this, the team first measured the filtration efficiency of N95 masks from different brands. The efficiency ranged between 95%-98%. After this, they sanitized these masks using either boiling water, ethanol, steam or had them washed in a washing machine. As previously predicted and confirmed, the decontamination procedure made the masks less efficient at filtering out minute particles.
The team then recharged a mask by placing it between two metal plate electrodes that charged it with an 800 volts per millimeter electric field strength. The electric field used was high so that the polypropylene mask fabric would become conductive, thus allowing electrical charges to be deposited on it. It was noted that the charges remained on the fabric even after the current was turned off and that it took an hour to fully charge a mask.
In addition to this, the team discovered when testing the filtration ability of recharged masks that the charging had restored 95% of the filtration effectiveness of the decontaminated N95 masks.
Even so, the inventor of the N95 mask, Peter Tsai, questions whether the whole process for testing the filtration degree was adequate. However, the team disagrees and stands by their results. The innovative team is applying for a patent currently, as well as exploring other fields that their study may be applied in, such as recharging air filtering systems and HVACs.
This discovery could make protecting frontline workers more affordable, and that is an outcome which biomedical companies like Predictive Oncology (NASDAQ: POAI) applaud since the innovation solves a pressing need.
Please see full terms of use and disclaimers on the BioMedWire website applicable to all content provided by BMW, wherever published or re-published: http://BMW.fm/Disclaimer
Since the coronavirus crisis was declared a pandemic, N95 masks, which are a design of personal protective equipment have been in short supply.
N95 masks as well as other masks used in the medical field use two filtration methods, electrostatic filtering and mechanical filtering using mask fibers. Electrostatic filtering uses stationary electric charges to attract and catch minute 0.3-micron particles such as fluid droplets that may contain viruses. N95 masks are also only for single day use as they become less effective at filtering out minute particles once the electrostatic charges that are present in the mask leak into the air.
Additionally, high humidity areas speed up the loss of efficiency of N95 masks. Other procedures, such as boiling or baking to decontaminate the masks or using fumigation machines or UV light towers also remove the masks’ electrostatic charge.
However, in a paper that was recently published in the Physics of Fluids journal, turns out you can recharge your N95 mask. Shankar Ghosh and his colleagues from the Tata Institute of Fundamental Research in Mumbai, India, and Dov Levine, discovered that decontaminated N95 masks can be recharged with a jolt of electricity, which restores the masks’ electrostatic charges.
Dov Levine, who is a physicist at Technion-IIT located in Haifa, Israel and the team also created a battery-powered, smart mask prototype that has a removable filter which can be charged continuously in order to maintain high filtration levels even after it’s been in use for hours.
To do this, the team first measured the filtration efficiency of N95 masks from different brands. The efficiency ranged between 95%-98%. After this, they sanitized these masks using either boiling water, ethanol, steam or had them washed in a washing machine. As previously predicted and confirmed, the decontamination procedure made the masks less efficient at filtering out minute particles.
The team then recharged a mask by placing it between two metal plate electrodes that charged it with an 800 volts per millimeter electric field strength. The electric field used was high so that the polypropylene mask fabric would become conductive, thus allowing electrical charges to be deposited on it. It was noted that the charges remained on the fabric even after the current was turned off and that it took an hour to fully charge a mask.
In addition to this, the team discovered when testing the filtration ability of recharged masks that the charging had restored 95% of the filtration effectiveness of the decontaminated N95 masks.
Even so, the inventor of the N95 mask, Peter Tsai, questions whether the whole process for testing the filtration degree was adequate. However, the team disagrees and stands by their results. The innovative team is applying for a patent currently, as well as exploring other fields that their study may be applied in, such as recharging air filtering systems and HVACs.
This discovery could make protecting frontline workers more affordable, and that is an outcome which biomedical companies like Predictive Oncology (NASDAQ: POAI) applaud since the innovation solves a pressing need.
Please see full terms of use and disclaimers on the BioMedWire website applicable to all content provided by BMW, wherever published or re-published: http://BMW.fm/Disclaimer
