Filters: Essential PPE Items
By: Seshadri Ramkumar, Professor, Texas Tech University, USA
The COVID-19 pandemic tested the domestic manufacturing capabilities of nations, particularly in the production of filters and other personal protective equipment (PPE).
Filters and protective garments are part of the advanced textiles sector, offering significant opportunities for manufacturers, even in developed economies. To support domestic manufacturing, the United States has imposed tariffs on imported face masks. With the new tariff set by President Donald Trump taking effect on March 4, the duty on face masks imported from China will be 35%.
Recent research at the Nonwovens and Advanced Materials Laboratory at Texas Tech University analyzed various face masks distributed by the U.S. government during the peak of the COVID-19 pandemic. The study focused on the filtration efficiency of different types of masks, including highly efficient facepiece respirators such as N95 and R95. The research utilized aerosolized particles of sizes comparable to viruses and bacteria.
Findings revealed that facepiece respirators offer the highest filtration efficiency, providing optimal protection for users. The study also demonstrated that well-fitting, high-quality three-layered face masks could effectively filter larger particles, such as those found in smoke scenarios. Additionally, results indicated that domestically produced masks often outperform imported alternatives in filtering larger particles.
According to the World Health Organization, 14% of global deaths are attributed to lung cancer, while 9% result from chronic pulmonary diseases. Comfortable and well-fitting multi-layered face masks can help mitigate these risks, particularly in high air pollution areas and wildfire smoke conditions, as recently experienced in California and cities like New Delhi.
Future research should focus on developing high-efficiency face masks using lightweight cotton nonwovens. Advancements in nonwoven technology, such as MicroPunch technology from DiloGroup, introduced at ITMA 2023, make this possible. The industry must prioritize innovation in comfort, reusability, and recyclability of facepiece respirators.
This research was featured as the cover article in the February 2025 issue of TAPPI Journal, a peer-reviewed, open-access publication by the Technical Association of the Pulp and Paper Industry.
The study was conducted with contributions from Faizur Rahman and Mirza Khyum.
