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Results of Far-UVC and Protective Textile Based System for Germ Free Angiography Units

Olcay, Ayhan; Albayrak, Serdar Baki; Akturk, Ibrahim Faruk; Yolay, Onur; Ozturk, Vedat; Yasar, Ozgur; Karabay, Mehmet; Mayisoglu, Herman; Mazlum, Mustafa; Bayer, Mehmet Cetin; Haziroglu, Ceyhun; Umihanić, Fadil

Abstract

Methods: A pre-post study design was implented at Bahçelievler Medicana Hospital during the peak of the Covid-19 pandemic, from February 11, 2021, to March 5, 2021. The study population consisted of 11 individuals diagnosed with coronary artery disease and 4 healthcare professionals without any diagnosed medical conditions. Among the 11 patients, 10 underwent coronary angiography, 1 underwent coronary stenting, and 1 underwent peripheral angiography. The angiography suite was equipped with the Initus-V Far-UVC system, and all procedures were conducted under this system. Skin erythema, ocular condition, and infection status were assessed prior to and immediately following exposure, with follow-up evaluations conducted 24 hours and 1 week later. Results: The average age of patients was 48 years, with a standard deviation of 7.35 years. Conversely, the average age of healthcare personnel was recorded at 36.75 years, with a standard deviation of 9.53 years. Notably, one patient tested positive for Covid-19 both prior to and after the procedure. In contrast, no healthcare personnel were found to be positive for Covid-19 infection at any point, either before or after the procedures were conducted. The textile clothing utilized in the Initus-V system is characterized by an Ultraviolet Protection Factor (UPF) that effectively filters out 98% of Far-UVC radiation, permitting only 2% to penetrate, thereby significantly reducing the risk of UVC exposure. Moreover, no discernible changes to the skin or eyes of any participants were attributable to exposure to 222nm UVC during or following the procedures. Conclusion: The Far-UVC system provides effective germicidal action without presenting risks in operating rooms, offering promising potential for a broad range of applications, including public transportation and hospital rooms. The implementation of this technology, coupled with Far-UVC-resistant textiles, may reduce the reliance on traditional epidemiological measures, which can have significant global economic and social impacts. Furthermore, this system offers a proactive solution for preventing the transmission of aerosolized pathogens, bypassing the delays associated with extensive human trials or complex regulatory processes.

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WJMI, 5(1), 2025 - WORLD JOURNAL OF MEDICAL INNOVATIONS | Available at www.worldjmi.com 32 Results of Far-UVC and Protective Textile Based System for Germ Free Angiography Units Ayhan Olcay1, Serdar Baki Albayrak1, Ibrahim Faruk Akturk2, Onur Yolay1,3, Vedat Ozturk4, Ozgur Yasar5, Mehmet Karabay6, Herman Mayisoglu7, Mustafa Mazlum8, Mehmet Cetin Bayer8, Ceyhun Haziroglu9, Fadil Umihanić10 1. R&D Department, Innoway R&D Kft., Budapest, Hungary. 2. Bakirköy Sadi Konuk Education and Research Hospital, İstanbul, Turkey. 3. Boğaziçi University Center for Targeted Therapy Technologies, İstanbul, Turkey. 4. İstanbul Aydin University, Department of Mechanical Engineering, İstanbul, Turkey. 5. Medicana Bahçelievler Hospital, Department of Ophthalmology, İstanbul, Turkey. 6. Medicana Bahçelievler Hospital, Infectious Diseases Department, İstanbul, Turkey. 7. Medicana Bahçelievler Hospital, Department of Dermatology, İstanbul, Turkey. 8. Vestel Home Appliances Research and Development Department, Manisa, Turkey. 9. School of Medicine, Marmara University, Istanbul, Turkey. 10. Istanbul University Cerrahpasa School of Medicine, Istanbul, Turkey. Article info Abstract PUBLIC HEALTH NEUROSURGERY Original study Article history: Accepted October 01, 2025 Published online October 12, 2025 Copyright © 2025 by WJMI All rights reserved Methods: A pre-post study design was implented at Bahçelievler Medicana Hospital during the peak of the Covid-19 pandemic, from February 11, 2021, to March 5, 2021. The study population consisted of 11 individuals diagnosed with coronary artery disease and 4 healthcare professionals without any diagnosed medical conditions. Among the 11 patients, 10 underwent coronary angiography, 1 underwent coronary stenting, and 1 underwent peripheral angiography. The angiography suite was equipped with the InitusV Far-UVC system, and all procedures were conducted under this system. Skin erythema, ocular condition, and infection status were assessed prior to and immediately following exposure, with follow-up evaluations conducted 24 hours and 1 week later. Results: The average age of patients was 48 years, with a standard deviation of 7.35 years. Conversely, the average age of healthcare personnel was recorded at 36.75 years, with a standard deviation of 9.53 years. Notably, one patient tested positive for Covid-19 both prior to and after the procedure. In contrast, no healthcare personnel were found to be positive for Covid-19 infection at any point, either before or after the procedures were conducted. The textile clothing utilized in the Initus-V system is characterized by an Ultraviolet Protection Factor (UPF) that effectively filters out 98% of Far-UVC radiation, permitting only 2% to penetrate, thereby significantly reducing the risk of UVC exposure. Moreover, no discernible changes to the skin or eyes of any participants were attributable to exposure to 222nm UVC during or following the procedures. Conclusion: The Far-UVC system provides effective germicidal action without presenting risks in operating rooms, offering promising potential for a broad range of applications, including public transportation and hospital rooms. The implementation of this technology, coupled with Far-UVC-resistant textiles, may reduce the reliance on traditional epidemiological measures, which can have significant global economic and social impacts. Furthermore, this system offers a proactive solution for preventing the transmission of aerosolized pathogens, bypassing the delays associated with extensive human trials or complex regulatory processes. Corresponding author. Prof. Dr. Ayhan Olcay, R&D Department, Innoway R&D Kft., Budapest, Hungary, e-mail: [email protected] Keywords: COVID-19, Far-UVC, Ultraviolet Germicidal Irradiation, public health WJMI, 5(1), 2025 - WORLD JOURNAL OF MEDICAL INNOVATIONS | Available at www.worldjmi.com 33 Introduction. Coronavirus disease 2019 (COVID-19) was first identified in December 2019 and declared a pandemic on March 11, 2020. Despite extensive efforts to contain the disease, COVID-19 has resulted in 753 million confirmed cases and over 6.8 million deaths as of January 30, 2023, (1). The rapid increase in cases, leading to severe pulmonary and extrapulmonary manifestations, bringing some healthcare systems to the brink of collapse (2-7). COVID-19 is believed to be transmitted through both direct contact and airborne routes (8). Thus, the implementation of innovative technologies is critical to preventing the spread of the disease in hospitals and public areas. This necessity is underscored by the virus's ability to remain viable in aerosols for up to three hours and the potential for transmission from asymptomatic carriers (2). Furthermore, lockdowns and social distancing measures have significantly disrupted the global economy, with pronounced effects in regions characterized by substantial income inequality (9). Ultraviolet germicidal irradiation (UVGI) is defined as the use of ultraviolet (UV) light in the germicidal range (wavelengths: 200–320 nm) for the disinfection of air and surfaces It is a proven method currently employed in high-risk settings (10), (11-13). Ultraviolet-C (UVC) radiation is the most effective and commonly used germicidal wavelength range of the ultraviolet spectrum (11). UVC light induces the formation of photoproducts, such as pyrimidine dimers, which cause structural distortions in DNA and disrupt RNA/DNA transcription and replication processes, effectively killing various microorganisms in different settings (12-15). In fact, UVGI was effectively used in tuberculosis wards in the past but has resurfaced as a popular choice during Covid-19 pandemic (16, 17). A low-pressure mercury-vapor arc lamp emitting about 254 nm is the most often utilized form of UV light for antimicrobial purposes; however, xenon lamp technology has also been used, which provides a broad UV spectrum. (3-5) These can be used for air disinfection either as duct irradiation or upper room UVGI (UV light projection in a room above people’s heads). These UV lights cannot be used in the presence of living organisms due to the risk of serious skin and eye problems (6, 7, 9, 10). Far-UVC (207 to 222 nm) represents an advanced form of UVC that is as effective at eliminating microorganisms as conventional germicidal UV light (18). Recent studies have demonstrated that Far-UVC exposure does not cause the skin and eye problems associated with conventional UVC exposure (18-21). Far-UVC light can penetrate only a few micrometers, which is sufficient to inactivate viruses and bacteria in biological materials as well as in the stratum corneum of the skin. It does not penetrate the stratum corneum or the ocular tear layer, thus not reaching living human cells in the skin or eyes. Thus, Far-UVC provides the same germicidal efficacy as conventional UVC but without the associated health hazards (18-21). Far-UVC light (207 or 222 nm) is produced by low-cost excimer lamps and has the potential to be used in crowded public locations (18, 22-24). Low-dose-rate Far-UVC can be an effective method for preventing aerosolized virus transmission in public areas (23). Currently, there are no operating rooms, intensive care units, or sterile settings utilizing UVC lamps with wavelengths of 200-222 nm. Objectives To evaluate the effects of the Initus-V Far-UVC system on the skin and eyes of individuals wearing safety goggles and UVC-protective ponchos or overalls, as well as the transmission of infection to healthcare workers in hospital settings. Methods The study is a pre-post design. The study was conducted in a single center at Bahçelievler Medicana Hospital during peak Covid-19 pandemic from 11.02.2021 to 05.03.2021. Ethical committee permissions were received and all patients were insured for trials. 11 individuals with coronary artery disease and 4 healthcare workers with no diagnosed condition volunteered to participate in the study. Participants signed an informed consent form. The participants' ages range from 25 to 75. Males made up 11 (73%) of the total participants, while females made WJMI, 5(1), 2025 - WORLD JOURNAL OF MEDICAL INNOVATIONS | Available at www.worldjmi.com 34 up 4 (27%). The exclusion criteria were: (i) skin disorders or skin-related malignancies, (ii) recent eye surgery, (iii) corneal and retinal abnormalities, (iv) glaucoma. Procedure Initus-V System Description and 222nm UVC light source. Initus-V system was developed collaboratively by InnowayRG Inc and Vestel Home appliances Inc. A patent application has been made to TURKPATENT in the partnership of these two companies (TR2020/07546). This approach allows for the instant deployment of Far-UVC technology without any regulatory authority conflict or restriction. The 222nm light source of Initus-V was produced by Vestel Inc. (Manisa, Turkey) and InnowayRG Inc. (Istanbul, Turkey) features a krypton-chloride (Kr-Cl) excimer lamp and an optical filter with a maximum output wavelength of 222nm and emission wavelengths ranging from 200 to 230nm. The unit consists of a lamp, air cooling fan, mirrors and a specialized band-pass filter. The attached filter effectively eliminates almost all wavelengths outside the dominant 222nm emission. The intensity of 222nm light was measured with an S-172 / UIT250 accumulated UV meter (Ushio Inc.) and was found to be maximum 2.23 uW/cm2 at the center and minimum 1.34 uW/cm2 at the distance of 2.5 meters (Figure 1). Figure 1. Initus-V’s 222 nm Far-UVC light source produced by Vestel and InnowayRg Inc. The maximum permissible 222nm UVC radiation limit The limit for those exposed to 222nm UVC in an 8-hour period determined by the International Commission on Non-ionizing Radiation Protection (ICNIRP) is approximately 22 mJ/cm2 (25). ACGIH, the American Association of Industrial Hygienists of the U.S. government, recently released an updated document and the daily irradiation limit of 222 nm was increased from 22 mJ/cm2 to 160 mJ/cm2 (eye corneal irradiation) and 478 mJ/cm2 (skin irradiation), which expands application of Far-UVC technology products (26). Textile fabric used in Initus-V system and UVC 222nm transmittance measurements. The transmittance of the 222 nm wavelength through the textile clothing (overalls) used in the Initus-V system was measured using a Mettler Toledo UV7 spectrophotometer. The results showed an average transmittance of 1.5%. Additionally, the textile clothing used in the Initus-V system possesses an Ultraviolet Protection Factor (UPF) of 50+, which quantifies the fabric's ability to block UV radiation, including both UVB and UVA rays. A UPF 50 fabric filters out 98% of UV radiation, allowing only 2% (1/50th) to pass through, thus significantly minimizing the risk of UV exposure (Figure 2). WJMI, 5(1), 2025 - WORLD JOURNAL OF MEDICAL INNOVATIONS | Available at www.worldjmi.com 35 Figure 2. Initus-V textile fabric overall 222nm wavelength transmittance measurements by Mettler Toledo UV7 spectrophotometer. Initus-V 222nm UVC source installation in the working environment and UVC exposure calculation. To ensure that the UVC exposure for a 170 cm tall operator remains within legal limits while wearing fabric overalls, Initus-V UVC sources should be positioned at least 220 cm above the ground. Measurements indicate that this setup keeps exposure within the daily permitted limit of 22 mJ/cm², considering 1.5% fabric permeability to the head area. This means that under the fabric, the UVC exposure will be 22 mJ/cm² over an 8-hour period, while the surface of the fabric will experience 1488 mJ/cm². These values are achieved at 50 cm from the Initus-V UVC source. Therefore, the devices must be placed more than 50 cm away from the operator's nearest body part. Operating Room/Intensive Care System with active Initus-V Far-UVC light setup safe for personnel to work in: The Initus-V system utilizes a 200-222nm UVC light source in conjunction with UVC-proof glasses and protective textile clothing while UVC is active in the environment. Despite several studies confirming the safety of Far-UVC light on skin and eyes in animal trials, we opted to incorporate textile and goggle protection to comply with ICNIRP's existing regulatory limits. With the lack of long-term human trials with far-UVC technology, regulatory organizations are highly hesitant to allow its usage in the presence of living individuals. WJMI, 5(1), 2025 - WORLD JOURNAL OF MEDICAL INNOVATIONS | Available at www.worldjmi.com 36 During trials operating rooms, intensive care units, emergency rooms or other sterile areas were illuminated with fixed or movable Initus-V UVC light sources emitting light in the 200-222 nm wavelength to prevent surgical field infection (Figure 3). During procedures, operators and auxiliary staff wore UVCprotective overalls and UVC-protecting goggles. The innovative textile ensures that human exposure to 222 nm UVC irradiation remains below regulatory limits, facilitating the use of Far-UVC in all conditions without the need for extensive human trials. Figure 3. The operating rooms requiring sterility are illuminated with fixed Initus-V UVC light sources that emit light within the 200-222 nm wavelength range. Additionally, movable UVC lamps are utilized to prevent surgical field infection. UVC-protective overalls are available in designs that cover the entire body and head, either with a front zipper or as a poncho for ease of movement and comfort. Patients in the intensive care unit or operating room were shielded with UVC protective covers (Figure 4,5) and, if necessary, additional UVC protective eyewear. WJMI, 5(1), 2025 - WORLD JOURNAL OF MEDICAL INNOVATIONS | Available at www.worldjmi.com 37 Figure 4. Operators and other auxiliary personnel wore UVC-protective overalls designed to cover the whole body and zippered in the front or as poncho for easier movement and comfort. Figure 5. Angiography suit was illuminated with Initus-V UVC light source for exposure measurements prior to initiating patient clinical studies. WJMI, 5(1), 2025 - WORLD JOURNAL OF MEDICAL INNOVATIONS | Available at www.worldjmi.com 38 Results Patients were older (48 ± 7.35) than healthcare personnel (36.75 ± 9.53) years. One patient was COVID19 positive both preand post-procedure. Healthcare personnel were not positive for Covid-19 infection neither before nor after the surgery. The average of total 222nm UVC exposure time was much shorter (23.2 ± 10 minutes) for patients than it was for healthcare workers (277.5 ± 18.93 minutes). There were no observed skin or eye changes due to 222nm UVC exposure in any participants. Follow-up questions concerning skin and ocular conditions were normal 24 hours and 1 week after the procedure. Discussion A serious rise in Health Care Associated Infections (HCAI) has dramatically increased healthcare costs. In 2000, HCAIs caused 5,000 deaths in the United Kingdom (UK) alone, causing a 1% increase in the total UK National Hospital budget (27). The US Centers for Disease Control and Prevention estimated the total costs in North America to be in excess of $6 billion ($US) for treating HCAIs and their associated complications (28). It is estimated that approximately 2.4 billion € are spent annually for treatment of HCAIs in Germany (29). Invasive angiography suit procedures are also mortal and costly. Pacemaker implantations are frequently performed permanent endocardial leads implantation infection rate is between 1% and 2%, but there are literatures reporting 0.13% to 12.6% rates. Implantable anti arrhythmic system numbers are increasing, and the National Hospital Discharge Survey revealed that between 1996 and 2003, the rates of hospitalization for infections of implantable antiarrhythmic systems increased faster than the rates of system implantations (30). TAVI is now routinely performed in angiography suits and TAVI related infective endocarditis is mortal and seen in 3.25% of cases. The most common complication is heart failure with a cumulative incidence of 37.1%. Enterococci are the most common causative organism isolated from 25.9% of cases followed by Staphylococcus aureus in 16.1% of cases. Appropriate sterility measures and antibiotic prophylaxis are standard procedures (31). Endovascular aneurysm repairs (EVAR) are also routinely performed in angiography suits and prosthesis infection rates are between 0.2% and 5% (32). Far-UVC technology has the potential to become standard angiography suit equipment to reduce implantable device infection rated as higher risk patients and procedures are progressively increasing in cardiology. Transmission of Far-UVC light at 200 nm from the cornea to the lens is predicted to be essentially zero. It has been observed that 207 nm UV light effectively kills MRSA, without causing significant damage to human cells, unlike conventional germicidal UV lamps (18-21). Furthermore, research involving Xpa knockout mice and wild-type mice subjected to repetitive 222 nm UVC irradiation, following a tumor-inducing protocol that produces tumors with broad-band UVB, showed no evidence of tumor induction (22). Contrary to significant side effects observed with traditional germicidal UV lamps, Research using a three-dimensional human skin model has shown that exposure to 207 nm UV light results in virtually no mutagenic UV-associated DNA lesions (18, 24). This suggests that Far-UVC sterilization can be safely conducted in environments with human presence. In a previous study, the effects of skin exposure to 222 nm UV radiation were evaluated using a device designed to sterilize equipment (Sterilray™ Health Environment Innovations, Dover, New Hampshire, USA). The study assessed the induction of skin erythema and cyclobutane pyrimidine dimers (CPD) in skin biopsies. Findings indicated that the UVC-emitting Sterilray not only induced erythema but also caused DNA damage in the form of CPDs, which are associated with skin cancer. These effects were observed at dosage levels below the threshold for bacteriostatic or bactericidal effects. This suggests that frequent, several-times-daily use of Sterilray irradiation is unlikely to be tolerated as a non-chemical antiseptic for human skin (33). A recent paper revealed that viable SARS-CoV-2 can be present in aerosols generated by a Covid-19 patient in a hospital room in the absence of an aerosol- WJMI, 5(1), 2025 - WORLD JOURNAL OF MEDICAL INNOVATIONS | Available at www.worldjmi.com 39 generating procedure and can thus serve as a source for transmission of the virus in this setting (34). Air samples were collected in a room within a designated Covid-19 ward, which had six air changes per hour. The exhaust air underwent triple filter treatment, coil condensation to remove moisture, and UV-C irradiation before 90% of the treated air was recycled back into the room. The air-samplers were stationed from 2 to 4.8 m away from the patients. This article suggests that despite maximum air filtering, aerosol transmission is possible from a 4.8-meter distance from a patient. The Initus-V system, capable of inactivating airborne viruses, can address this issue irrespective of the ventilation quality. In a previous study, Far-UVC scenario with 5 lamps performs substantially better than even a higher flow HEPA-based air cleaner. A potential advantage of FarUVC over air cleaners is that it may not require “good” air mixing within the room (35). Low-dose-rate far-UVC is a promising tool to prevent spread of aerosolized viruses in public locations. However, stringent regulations regarding UVC exposure present significant challenges. Implementing Far-UVC technology with UVC-resistant textiles, as utilized in the Initus-V system, appears to be a viable solution for introducing this technology into public spaces without waiting for long-term human trial results or regulatory changes (23). There were no observed skin or eye changes due to 222 nm UVC exposure in any participants during or after the procedures in angiography suit. Contrary to the current technique, UVC systems operating at wavelengths of 200-222 nm exhibit high reliability, minimal health risks, ease of installation, and effective performance without reliance on consumables. By integrating this system with clothes and covers made of UVC-proof fabric as utilized in Initus-V, we address concerns about long-term damage and enable safe, immediate operation under UVC light. Our proposed system includes UVC-protected wearable fabrics and clothing, patient and operating room covers, UVCproof glasses, and laboratory lighting within the 200222 nm range. Limitations In our study we did not want to perform skin biopsy examination pre and post exposure in staff or patients due to invasive nature of procedure but limited assessment by infectious disease, dermatology and ophthalmology examinations. Our study was a preliminary safety study and enrolled only angiography and stent patients instead of higher risk invasive cardiological procedures. Pre and post procedure microbiologic culture examinations were not performed. Statement of Ethics IRB information: The present study was approved by the Local Ethics committee of Ataturk University [2020/498]. All the steps of this study was met the standards of Declaration of Helsinki and Good Clinical Practice Guidelines. Informed Consent The written informed consent to participate in the study has been obtained from all adult participants and all vulnerable participants' parent/legal guardian/next of kin. Conflict of interests The authors declare that there is no conflict of interest regarding the publication of this article. Initus-V system was developed by InnowayRG Inc and Vestel Home appliances Inc. A patent application has been made to TURKPATENT in the partnership of these two companies. (TR 2020/07546) Ayhan Olcay, Serdar Baki Albayrak, Onur Yolay are founders of InnowayRG Inc. Mehmet Cengiz Akbulbul and Mehmet Cetin Bayer are inventors. Mehmet Faruk Akturk and Fadil Umihanić report no conflicts of interest. Financial Disclosure The authors have not declared financial support. WJMI, 5(1), 2025 - WORLD JOURNAL OF MEDICAL INNOVATIONS | Available at www.worldjmi.com 40 Author Contributions Ayhan Olcay contributed to the study as design of study, sample collection, critical analysis, text writing and histologic examination and contributed 25% each. Serdar Baki Albayrak contributed to the study as design of study and critical analysis and contributed 15%. İbrahim Faruk Akturk, Onur Yolay, Vedat Ozturk, Ozgur Yasar, Mehmet Karabay, Herman Mayisoglu, Mehmet Cetin Bayer, Mustafa Mazlum, Ceyhun Haziroglu and Fadil Umihanić contributed to the study as sample collection and text writing and contributed 6% each. Data Availability Statement All data generated or analyzed during this study are included in this article. Further enquiries can be directed to the corresponding author. References 1. 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