Comparative analysis of filtration ability of different cloth masks

ABSTRACT

Introduction: The effectivity of cloth masks is one of the major concerns during pandemic. In this study, the filtration ability of different cloth masks was compared. Materials and Methods: We examined the filtration ability of different cloth masks in "Touch Screen Aerosol Photometer"DOP3500 machine by testing 0,3-0,5 μm diameter standart "aerosol"particle at mask factory (MAKSAM) of Mechanical and Chemical Industry Company located in Ankara. In order to show the difference in filtration ability of the cloth maskes clearly, particule size was defined as 0,3-0,5 μm. Pure silk 100%, 80% silk + 20% polyester, 100% satin, 100% polyester, 100% cotton, 100% bamboo and 50% cotton + 50% polyester were compared. Cloth masks made from these materials were tested three times;before washing, after ten times washing and combined using with a medical mask. Results: N95/FFP-2 respirator was used as a "positive control"with a filtration ability of 99.7%. Measurable filtration ability of total particle counts was 18.2% of three layered medical mask. When we tested double medical mask, reduction of total particle counts reached to 31.6%. According to our result, we conclude that wearing double medical mask is more protective than wearing a single medical mask. Measureable reduction of total particle counts were different for all tested cloth masks. Cloth masks were tested second time after 10 times washing. Un-washed cloth mask made from 80% silk + 20% polyester was found to be protective, however after ten times washing particle counts of the same mask reduced markedly. Measurable reduction of total particle counts were also reduced after ten times washing of cloth masks made from 100% satin and 100% polyester. The most efficient cloth mask for blocking particules was 100% cotton after ten times washing. Conclusion: Our study offers evidence in favor of synthetic and polyester materials are not suitable for cloth masks since their filtration ability is reduced after multiple washing. Instead, use of cotton masks is more preventive than the others because of its increased filtration ability after washing. Combined wearing of medical mask and cloth mask together resulted in increased efficacy of filtration ability of both masks. We conclude that, wearing double mask is more effective than wearing a single mask when we consider the actual status of the pandemic with widespread distribution of mutant viruses and the high number of infected individuals in the public.