ABSTRACT
Airborne exposure has been highlighted during the COVID-19 pandemic as a probable infection route. This experimental study investigates different protection methods at an office workstation, where the concentration characteristics are studied under the mixing ventilation conditions. The protection methods were the room air purifier, personal air purifier, face mask, and workstation partition panels. In experiments, the breathing machine, nebulizer, and syringe pump was used to generate an aerosol distribution of paraffin oil into the room. The breathing thermal manikin and the thermal dummy simulated the exposed and infected person, respectively. The concentration characteristics were measured from the manikin breathing zone. The temporal concentration characteristics were measured from zero concentration to steady-state conditions. The study provides insights into the effects of different protection methods for occupational health and safety decision-making for office indoor environments. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.
ABSTRACT
The COVID-19 mandates an increase in the use of service robots as human replacements in polluted areas. This task encompasses logistics, patient care, and disinfection, all of which limit the danger of human exposure to the extremely infectious and fatal illness. To fulfil the criteria of the World Health organization, the certified sanitizing system is a method for decontaminating individuals and surfaces. In this work, an automated sanitizing equipment is designed. The equipment spray a sanitizer solution is the area to be disinfected. The transportable sanitizing unit is mounted to the robot's head. SolidWorks software is used to design the equipment. Design included identifying main parts of the system, deciding about material for different parts, and 3D design of each of the parts. Finally, the assembly of the complete system is presented. The finalized product was then simulated in MATLAB. Analysis of the system included flowrate, pressure, and maximum spray distance. Results obtained are consistent with requirements. © 2022 IEEE.
ABSTRACT
Facemasks are important tools for fighting against disease spread, including Covid-19 and its variants, and some may be treated with per- and polyfluoroalkyl substances (PFAS). Nine facemasks over a range of prices were analyzed for total fluorine and PFAS. The PFAS compositions of the masks were then used to estimate exposure and the mass of PFAS discharged to landfill leachate. Fluorine from PFAS accounted only for a small fraction of total fluorine. Homologous series of linear perfluoroalkyl carboxylates and the 6:2 fluorotelomer alcohol indicated a fluorotelomer origin. Inhalation was estimated to be the dominant exposure route (40%-50%), followed by incidental ingestion (15%-40%) and dermal (11%-20%). Exposure and risk estimates were higher for children than adults, and high physical activity substantially increased inhalation exposure. These preliminary findings indicate that wearing masks treated with high levels of PFAS for extended periods of time can be a notable source of exposure and have the potential to pose a health risk. Despite modeled annual disposal of 29-91 billion masks, and an assuming 100% leaching of individual PFAS into landfill leachate, mask disposal would contribute only an additional 6% of annual PFAS mass loads and less than 11 kg of PFAS discharged to U.S. wastewater. © 2022 American Chemical Society.