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Purpose: It is now clear that the COVID-19 viruses can be transferred via airborne transmission. The objective of this study was to attempt the design and fabrication of an AMBU ventilator with a negative pressure headbox linked to a negative pressure transporting capsule, which could provide a low-cost construction, flexible usage unit, and also airborne prevention that could be manufactured without a high level of technology.Method: The machine consists of an automated AMBU bag ventilator, a negative pressure headbox, and a transporting capsule. The function and working duration of each component were tested.Results: The two main settings of the ventilator include an active mode that can be set at the time range of 0 s–9 h 59 min 59 s and a resting mode, which could work continuously for 24 h. The blower motor and battery system, which were used to power the ventilator, create negative air pressure within the headbox, and the transporting capsule, could run for at least 2 h without being recharged. The transporting capsule was able to create an air change rate of 21.76 ACH with-10 Pa internal pressure.Conclusion: This automated AMBU ventilator allowed flow rate, rhythm, and volume of oxygen to be set. The hazardous expired air was treated by a HEPA filter. The patient’s transporting capsule is of a compact size and incorporates the air treatment systems. Further development of this machine should focus on how to link seamlessly with imaging technology, to verify standardization, to test using human subjects, and then to be the commercialized.

Purpose Many autopsies, including COVID-19 cases, will be carried out where the cause of death, including COVID-19 cases, is unknown and the mortuary staffs will possibly be exposed to infectious bone dust and secretions. To help our funeral colleagues minimize their risk of infection, this manipulator was created to help prevent such serious events, as well as other conditions related to airborne diseases. This article provides some technical details necessary for creating an autopsy saw, including the machinery design, control system design, specification of devices, and other abilities of this machine. Methods The manipulator consists of a control system, linear actuator motors, a gearbox with DC gear motor, DC gear servo coreless motor, and the out-runner brushless DC electric motor. Results The results showed that the manipulator can be assembled to fit to, and be removed from, an autopsy bed without drilling into the bed surfaces. There is adjustment of the cutting range, both vertically and horizontally, via a remote control. The saw frame can be rotated through 360°for skull and tissue cutting. The saw blade depth can be adjusted from 0 to 3 cm. The rotational speed of the saw blade can be regulated from 0 to 10,080 RPM. The cutting procedure can be controlled remotely, up to 20 m away from the manipulator. Conclusion In future projects, the instrument design should allow control incorporating "Internet of things" technology, be constructed under a multipurpose autopsy machine concept, and also autonomously conduct a full autopsy procedure.

This study aimed to focus on the design and development of low-cost do-it-yourself (DIY) air purifiers, using a ventilating fan, air pump, water pump, and an ultrasonic generator that can be used during the haze pollution. Six types of household air purifiers were fabricated. The amount of particulate matter (PM) and carbon dioxide (CO 2 ) levels were recorded at 0, 10, 20, 30, and 60 min (min), then, repeated 3 times. After 10 min of the 3rd experiment of each study, the last measurement of air pollution would be recorded. The results showed at 60 min, the high-efficiency particulate air (HEPA) filter and electrostatic fiber was the best technique regarding reduction of PM and CO 2 levels. The highest PM reduction rate had occurred at 30 min using an air pump procedure (99.330 to 100%). The CO 2 levels of all experiments had fluctuated at different times. After 10 min of a closed machine, PM levels of all air purifier systems were decreased, except HEPA filter and electrostatic fiber types. In conclusion, the best method for reducing particulate matter and cost without taking humidity into account is an air pump technique, whereas the HEPA filter and electrostatic fiber method is the best choice for lowering PM levels without increasing humidity and vapor production.

Purpose: This study aimed to focus on the design and development of low-cost DIY air purifiers, using a ventilating fan, air pump, water pump, and an ultrasonic generator, with regard to filtration efficacy and also cost-effectiveness that can be used during the COVID-19 pandemic and haze pollution. Methods: Six types of household air purifiers, incorporating a HEPA filter, a HEPA filter & electrostatic fiber, an air pump, an air pump & ultrasonic wave, a water pump, and a water pump & ultrasonic wave, were fabricated. The amount of particulate matter (PM) and CO2 levels were recorded at 0, 10, 20, 30, and 60 min, then, repeated 3 times. After 10 min of the 3rd experiment of each study, the last measurement of air pollution would be recorded. Results: At 60 min, the HEPA filter & electrostatic fiber showed the best performance regarding reduction of PM and CO2 levels. The highest PM reduction rate had occurred at 30 min using an air pump procedure (99.330 to 100%). The CO2 levels of all experiments had fluctuated at different times. After 10 min of a closed machine, HEPA filter & electrostatic fiber revealed the highest rate of PM elevation, while PM levels of all water-based purifier systems were decreased. A water pump and air pump were the cheapest air cleaners, when taking into account maintenance expenses and electricity charges. Conclusion: An air pump is the optimum method for reducing particulate matter at minimum cost but without the benefit of reduced humidity, while the HEPA filter & electrostatic fiber is the best system to decrease PM levels, but this requires an enclosed structure at the inlet to prevent dust coming back into the room. As filtration efficiency is increased by the use of filters & electrostatic fiber mechanisms, the more expensive the system becomes.