ABSTRACT
This study investigated upper-room germicidal ultraviolet (UR-GUV) light application in a music rehearsal room with a high ceiling (7.5 m). The focus was on the influences of the elevation and height of UV zone on disinfection of airborne viruses. This study assumed a uniform UV fluence rate of 0.2 W/m2 in the UV irradiation zone. According to the Computational Fluid Dynamics (CFD) results, average viral concentrations (Ca), fraction remaining (FR), and equivalent air exchange rate (λe) attributed to GUV, have power relationships with UV zone height. Ca and FR decreased with UV zone height, while λe did the opposite. UV zone elevation showed little influence on UR-GUV performance, indicating well-mixed air in the rehearsal room. High ceiling makes it possible to achieve adequate UV dose by increasing both UV zone height and UV light intensity. Using open fixtures improved energy efficiency and reduced operational costs of the UR-GUV system. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.
ABSTRACT
The world is currently experiencing a crisis, caused by SARS-CoV-2 and a viral mutation. Given this, the mechatronic system is proposed that allows disinfecting contaminated surfaces. This device makes it possible to disinfect polyethylene terephthalate (PET) bottles by applying short-wave UVC rays from 200 to 280 nm, which generates a germicidal effect. The machine consists of a UVC chamber, transport, and a control system. For this, the methodology of the Association of German Engineers (VDI 2206) was used, taking into account the Inventor, TIA Portal, and Factory IO software, managing to develop the system whose light-emitting diodes inside the camera project type C ultraviolet light, camera protected by strips of plastic sheet (ABS) acrylonitrile butadiene styrene anti-ultraviolet light that blocks the projection wave up to 98% of the radiation;the recycled PET bottles are moved through a linear conveyor belt that supports a maximum weight of 200 kg, controlled by a control panel. Obtaining the results in this research focused on the design of the prototype, with a feasible structural system thanks to its maximum efficiency in the disinfection process. It is concluded that it is feasible to design a machine that projects ultraviolet rays to disinfect recycled PET bottles to eliminate viruses, parasites, fungi, and bacteria. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
ABSTRACT
Coronavirus (COVID-19) is an infectious illness due to serious respiratory trouble. It is impacted numerous humans and has asserted the living expectancy of a greater number of persons from all over the planet. The maturation period of this virus, on typically about 5-6 days but it might also be up to 2 weeks. Throughout this period, the individual may not feel any indications but could still be transmissible. A person could develop this disease if he/ she inhales the virus while a diseased person/ virus carrier within close vicinity sneezes or coughs otherwise tapping an infected place in addition to afterward again his/ her eyes, nose or mouth. To prevent this, the region of the COVID-19 patient must be decontaminated with virucidal disinfectants, such as and 0.05% sodium hypochlorite (NaClO) and ethanol-based products (at least 70%) an optional technique used is UV light sterilization. Ultraviolet (UV) sterilization technology is used to help reduce micro-organisms that can remain on surfaces after basic sprinkling to the minimum amount. The proposed work has established an UV robot or UV bot to perform decontamination in an operating room or in-patients room. Three 19.3-watt UV lights are positioned in a 360-degree circle on the UV bot platform. It used an integrated system based on a microprocessor and a metal frame to aid in navigation in a fixed path to avoid barriers. In addition, a sanitizer dispenser is also included to clean the viral organisms, which is spread through the water droplets of the patient. © 2022 IEEE.
ABSTRACT
Air disinfection using germicidal ultraviolet light (GUV) has received increasing attention during the COVID-19 pandemic. GUV uses UVC lamps to inactivate microorganisms, but it also initiates photochemistry in air. However, GUV's indoor-air-quality impact has not been investigated in detail. Here, we model the chemistry initiated by GUV at 254 ("GUV254”) or 222 nm ("GUV222”) in a typical indoor setting for different ventilation levels. Our analysis shows that GUV254, usually installed in the upper room, can significantly photolyze O3, generating OH radicals that oxidize indoor volatile organic compounds (VOCs) into more oxidized VOCs. Secondary organic aerosol (SOA) is also formed as a VOC-oxidation product. GUV254-induced SOA formation is of the order of 0.1-1 μg/m3 for the cases studied here. GUV222 (described by some as harmless to humans and thus applicable for the whole room) with the same effective virus-removal rate makes a smaller indoor-air-quality impact at mid-to-high ventilation rates. This is mainly because of the lower UV irradiance needed and also less efficient OH-generating O3 photolysis than GUV254. GUV222 has a higher impact than GUV254 under poor ventilation due to a small but significant photochemical production of O3 at 222 nm, which does not occur with GUV254. © 2022 American Chemical Society.
ABSTRACT
During the period of COVID-19, it is still inevitable for people to contact with each other based on the consideration of economic development. Therefore, the health management measures for staying in the hotel have become an important part of epidemic prevention. As we all know, ultraviolet (UV) light is an effective disinfection and sterilization method, which has been widely used in many applications. In this paper, a hotel anti-epidemic management system is proposed to disinfect the used rooms by using UV LEDs through WiFi communication with the front desk computer, and therefore it can protect quests from virus infection. © 2022 IEEE.
ABSTRACT
Since COVID-19 became a global pandemic, improving air quality has been increasingly important to mitigate the transmission of pathogenic aerosols. Air filters such as MERV filters have been widely used in heating, ventilation, and air conditioning (HVAC) systems to clean inlet air. In recent years, ultraviolet (UV) light has been used for decontamination and disinfection in various applications, including indoor air cleaning, e.g., upper-room ultraviolet germicidal irradiation (UVGI). There are a variety of air purification devices available in the market, with some incorporating UV technology. However, many of them are not formally tested and certified for their effectiveness in mitigating airborne pathogens and particulate matter. The research's objectives are to (1) evaluate, design, and upgrade an existing air filtration device (~2,200 CFM) with the addition of UV-C lamps;(2) test the effectiveness of the upgraded device in mitigating airborne pathogens (bacteria) and particulate matter (PM) in real scenario (poultry farm). The testing results of air quality are expressed in particular matter (PM) levels and colony-forming units (CFUs). The preliminary data showed that both MERV-8 & MERV 13 and UV-C lamps can inactivate up to 100% of airborne bacteria, and the device can remove over 95% of total PM after treatment in a ~150-layer room. © 2022 ASABE. All Rights Reserved.
ABSTRACT
With the global coronavirus pandemic still persisting, the repeated disinfection of large spaces and small rooms has become a priority and matter of focus for researchers and developers. The use of ultraviolet light (UV) for disinfection is not new;however, there are new efforts to make the methods safer, more thorough, and automated. Indeed, continuous very low dose-rate far-UVC light in indoor public locations is a promising, safe and inexpensive tool to reduce the spread of airborne-mediated microbial diseases. This paper investigates the problem of disinfecting surfaces using autonomous mobile robots equipped with UV light towers. In order to demonstrate the feasibility of our autonomous disinfection framework, we also present a teleoperated robotic prototype. It consists of a robotic rover unit base, on which two separate UV light towers carrying 254 nm UVC and 222 nm far-UVC lights are mounted. It also includes a live-feed camera for remote operation, as well as power and communication electronics for the remote operation of the UV lamps. The 222 nm far-UVC light has been recently shown to be non-inammatory and non-photo carcinogenic when radiated on mammalian skin, while still sterilizing the coronavirus on irradiated surfaces. With far-UVC light, disinfection robots may no longer require the evacuation of spaces to be disinfected. The robot demonstrates promising disinfection performance and potential for future autonomous applications. © 2022 SPIE. All rights reserved.
ABSTRACT
The emergence of COVID-19 pandemic led to an increase in establishing methods of sterilization and prevention, and also in the searching for sterilization methods at the lowest cost and most effective in eliminating viruses. Robots are widely used in many fields including the sterilization to reduce the risk to human life. This work presents a design and implementation of robot for automatic surface disinfecting using Ultraviolet (UV) lights. Arduino UNO R3 is used as micro controller to control the movement of the mobile robot and three ultrasonic sensor which used to avoid robot collision with obstacles. UV lights are used in the sterilization processes of surfaces, air and water, as it ruptures the DNA of bacteria or viruses and thus prevents it from reproduce. Eight UV lights are used in this research work which are fixed around the mobile robot. The results showed the low cost with robot using for surface disinfecting can be obtained with using simple sensors and actuators components and UV lights, as well as being safer for humans than using chemical disinfectants. © 2022 IEEE.
ABSTRACT
The COVID-19 pandemic has generated great interest in ultraviolet (UV) disinfection, particularly for air disinfection. Although UV disinfection was discovered close to 90 years ago, only very recently has it reached the consumer market and achieved much acceptance from the public, starting in the 2000s. The current UV light source of choice has been almost exclusively a low-pressure mercury vapor discharge lamp. Today, however, with emerging deep-UV (DUV) chip-scale technologies, there has been a significant advancement, along with ever-increasing interest, in the development and deployment of disinfection systems that employ compact devices that emit in the deep-UV spectral band (200- 280 nm), including UV light-emitting diodes (LEDs) and cathodoluminescent (CL) chips. This perspective looks into competing UV technologies (including mercury lamps and excimer lamps as benchmarks) on their optical merits and demerits and discusses the emerging chip-scale technologies of DUV electroluminescent and cathodoluminescent devices, comparing them against the benchmarks and providing an overview of the challenges and prospects. The accelerating progress in chip-scale solutions for deep-UV light sources promises a bright future in UV disinfection.
ABSTRACT
Robots are being increasingly used in the fight against highly-infectious diseases such as Ebola, MERS, and SARS-CoV-2. Many of these robots use ultraviolet lights mounted on a mobile base to inactivate the pathogens. While the lights are generally effective at irradiating open spaces and walls, they are less effective when it comes to horizontal surfaces, because of the orientation of the light sources. This can be problematic for pathogens such as Ebola, where transmission via contaminated work surfaces, which are often horizontal, is a concern. In this paper, we describe the design, implementation, and testing of an ultraviolet light disinfection system implemented on a mobile manipulator robot designed to address the problem of horizontal surface disinfection. A human supervisor designates a surface for disinfection, the robot autonomously plans and executes an end-effector trajectory to disinfect the surface to the required certainty, and then displays the results for the supervisor to verify. We also provide some background information on Ultraviolet Germicidal Irradiation (UVGI) and describe how we constructed and validated models of ultraviolet radiation propagation and accumulation in our system. Finally, we describe our implementation on a Fetch mobile manipulation platform, and discuss how the practicalities of implementation on a real robot affect our models. © 2021 IEEE.
ABSTRACT
Recently, the outbreak of COVID-19 once again has brought public health issues back to the forefront, emphasizing the importance of public health and the threat posed by public health problems to the health of people [1]. As public facilities become more and more developed and advanced, it is absolutely necessary to maintain their sanitary level. In this epidemic, contact infection in confined space is one of the main transmission routes of the virus;the frequently used button area inside the elevator therefore has a very high risk of infection. With the goal of being independent of the internal circuit of the elevator, not hindering the use of the elevator and not relying on the initiative of the user, this paper has carried out practice and research on reducing the contact infection caused by the operation of the elevator button. This paper mainly includes the analysis on the advantages and disadvantages of existing schemes, the introduction of a non-contact ultraviolet elevator button disinfection device based on image recognition and Arduino, the influence of light intensity on the accuracy of image recognition in this device, and the mathematical modeling related to the time cost of the better scheme. © 2021 IEEE