CAGAYAN DE ORO CITY, June 26 The Department of Science and Technology (DOST)-10 recently evaluated the efficiency of a local invention made to disinfect facemasks.
Engr. Elpidio M. Paras, CEO of Parasat Cable TV and inventor, developed the Parazapp UV Disinfection Cabinet. It is a portable and low-cost disinfecting equipment that is composed of locally-available materials such as Stainless Steel Cabinet, Timer System, and UV-C Germicidal Lamps.
Engr. Paras collaborated with DOST-10 through the latters Regional Standards and Testing Laboratories (RSTL) for the initial evaluation of the germicidal properties and initial determination of the optimal exposure time for the Parazapp.
The RSTL team treated N95 Face Mask samples with Escherichia Coli (E. coli) bacteria and subjected the samples to different exposure times from 30 seconds to five (5) minutes.
The Parazapp achieved 83 % to 97 % reduction of E. coli populations when used for five (5) minutes.
Through statistical methods, the team also estimated the proper exposure time needed to achieve higher reduction levels. At least 24 minutes of exposure inside the Parazapp may be needed to achieve a 99.99 % reduction of E. coli populations in the masks, and at least 38 minutes may be needed to achieve 99.9999% reduction.
It is worth noting that disinfection through UV radiation also has its limitations. UV disinfection is most effective for flat, non-porous surfaces, and transparent substances. PPEs that are multi-layered and made of opaque materials may not achieve proper disinfection. UV radiation also poses threats of skin and eye damage to operators when exposed without protection.
The US Environmental Protection Agency requires at least 99.9999% reduction of bacteria to qualify as disinfection. This shows that the Parazapp has the potential for disinfection of E. coli bacteria and other microbes in masks.
With the current rise of COVID-19, the Parazapp can also be potentially used to disinfect viruses in PPEs and other materials. But this requires further research and development with appropriate methods, testing equipment, and facilities. (Reymart T. Deligero, DOST-X)