Beautiful Virgin Islands

Tuesday, Jun 24, 2025

Double-Masking Can Be Potent To Protect People From Covid

Double-Masking Can Be Potent To Protect People From Covid

The findings published in JAMA Internal Medicine also states that the reason for the enhanced filtration is not about adding too many layers of cloth but eliminating any gaps or poor-fitting areas of a mask.
A new study by the University of North Carolina Health Care shows that wearing two face coverings can nearly double the effectiveness of filtering out SARS-CoV-2-sized particles, preventing them from reaching the wearer's nose and mouth and causing COVID-19.

The findings published in JAMA Internal Medicine also states that the reason for the enhanced filtration is not about adding too many layers of cloth but eliminating any gaps or poor-fitting areas of a mask.

"The medical procedure masks are designed to have very good filtration potential based on their material, but the way they fit our faces isn't perfect," said Emily Sickbert-Bennett, PhD, associate professor of infectious diseases at the UNC School of Medicine and lead author of the study.

To test the fitted filtration efficiency (FFE) of a range of masks, UNC researchers worked with James Samet, PhD, and colleagues in the USEPA Human Studies Facility on the campus of UNC-Chapel Hill. There they filled a 10-foot by 10-foot stainless-steel exposure chamber with small salt particle aerosols and had researchers don combinations of masks to test how effective they were at keeping particles out of their breathing space.

Each individual mask or layered mask combination was fitted with a metal sample port, which was attached to tubing in the exposure chamber that measured the concentration of particles entering the breathing space underneath the researcher's mask. A second tube measured the ambient concentration of particles in the chamber. By measuring particle concentration in the breathing space underneath the mask compared to that in the chamber, researchers determined the FFE.

"We also had the researchers in the chamber undergo a series of range-of-motion activities to simulate the typical motions a person may do throughout their day -- bending at the waist, talking, and looking left, right, up and down," said Phillip Clapp, PhD, an inhalation toxicologist in the UNC School of Medicine who has been testing mask FFE with Sickbert-Bennett since the pandemic began.

According to their findings, the baseline fitted filtration efficiency (FFE) of a mask differs from person to person, due to each person's unique face and mask fit. But generally, a procedure mask without altering the fit is about 40-60 per cent effective at keeping COVID-19-sized particles out. A cloth mask is about 40 per cent effective.

Their recent findings on doubling of face masks show that when a cloth mask is placed over a surgical mask, the FFE improved by about 20 per cent, and improved even more with a snug-fitting, sleeve-type mask, such as a gaiter. When layered over procedure masks, cloth masks improve fit by eliminating gaps and holding the procedure mask closer to the face, consistently covering the nose and mouth. When a procedure mask is worn over a cloth mask, FFE improved by 16 per cent.

"We've found that wearing two loosely fitted masks will not give you the filtration benefit that one, snug-fitting procedure mask will," Sickbert-Bennett said. "And with the current data supporting how effective mask-wearing is at preventing the spread of COVID-19, the best kind of double-masking is when you and the person you are interacting with are each correctly wearing a very snug-fitting mask."
Newsletter

Related Articles

Beautiful Virgin Islands
0:00
0:00
Close
Germany and Italy Under Pressure to Repatriate $245bn of Gold from US Vaults
Airlines Evaluate Flight Cancellations Amid Escalating US-Iran Tensions
Starmer Invites Innovators to Join Government Talent Scheme
UK Economy’s Strong Opening Quarter Shows Signs of Cooling
Harrods Seeks Court Order to Secure Al Fayed Estate for Victims
BA and Singapore Airlines Cancel Dubai Flights Amid Middle East Tensions
Trump Faces Backlash from MAGA Base Over Iran Strikes
Meta Bets $14 B on Alexandr Wang to Drive AI Ambitions
WATCH: Israeli forces show the aftermath of a massive airstrike at Iran's Isfahan nuclear site
FedEx Founder Fred Smith, ‘Heart and Soul’ of the Company, Dies at 80
Chinese Factories Shift Away from U.S. Amid Trump‑Era Tariffs
Pimco Seizes Opportunity in Japan’s Dislocated Bond Market
Labubu Doll Drives Pop Mart to Status as China’s Most Valuable Toy Maker
Global Coal Demand Defies Paris Accord Goals
We have new information and breaking details to share about what is shaping up to be a historic air campaign tonight
Six Massive Bombs Dropped on Fordow; Trump: 'A Historic Moment for the U.S., Israel, and the World'
Fordow: Deeply Buried Iranian Enrichment Site in U.S.–Israel Crosshairs
United States Conducts Precision Strikes on Iran’s Nuclear Sites
US strikes Iran nuclear sites, Trump says
Pakistan to nominate Trump for Nobel Peace Prize.
BBC Demands Perplexity AI Immediately Stop Using Its Content
Telegram Founder: I Will Leave My Fortune to Over 100 of My Children
Political Turmoil Resurfaces in Belgium Amid Economic Concerns
Fed policymakers divided on timing of interest rate cuts
Trump signals imminent agreement with Harvard University
Inheritance tax referendum alarms Swiss billionaire community
Japan cancels bilateral security meeting amid US defence demands
AI skeptic Emily Bender warns that ‘the emperor has no clothes’
Israel Confirms Assassination of Quds Force Commander in Tehran
16 Billion Login Credentials Leaked in Unprecedented Cybersecurity Breach
Senate hearing on who was 'really running' Biden White House kicks off
Iranian Military Officers Reportedly Seek Contact with Reza Pahlavi, Signal Intent to Defect
FBI and Senate Investigate Allegations of Chinese Plot to Influence the 2020 Election in Biden’s Favor Using Fake U.S. Driver’s Licenses
Vietnam Emerges as Luxury Yacht Destination for Ultra‑Rich
Plans to Sell Dutch Embassy in Bangkok Face Local Opposition
China's Iranian Oil Imports Face Disruption Amid Escalating Middle East Tensions
Trump's $5 Million 'Trump Card' Visa Program Draws Nearly 70,000 Applicants
DGCA Finds No Major Safety Concerns in Air India's Boeing 787 Fleet
Airlines Reroute Flights Amid Expanding Middle East Conflict Zones
Elon Musk's xAI Seeks $9.3 Billion in Funding Amid AI Expansion
Trump Demands Iran's Unconditional Surrender Amid Escalating Conflict
Israeli Airstrike Targets Iranian State TV in Central Tehran
President Trump is leaving the G7 summit early and has ordered the National Security Council to the Situation Room
Taiwan Imposes Export Ban on Chips to Huawei and SMIC
Israel has just announced plans to strike Tehran again, and in response, Trump has urged people to evacuate
Netanyahu Signals Potential Regime Change in Iran
Juncker Criticizes EU Inaction on Trump Tariffs
EU Proposes Ban on New Russian Gas Contracts
Analysts Warn Iran May Resort to Unconventional Warfare
Iranian Regime Faces Existential Threat Amid Conflict
×