A miniature air “curtain” to help stop the spread of COVID-19 in hospitals and other healthcare facilities where social distancing or mask-wearing is not possible has been developed.
The Desktop Air Curtain System (DCAS) can block all incoming aerosol particles, say the Japanese scientists behind it.
Study co-author Kotaro Takamure said: “We envision this system will be effective as an indirect barrier for use in blood testing laboratories, hospital wards, and other situations where physical distancing sufficient cannot be maintained, such as at a reception desk.”
An air curtain, or air door, is a fan-powered ventilation system that creates a seal above an entrance.
Hospitals use them to prevent ambulance fumes and other contaminants from reaching the interior of an emergency room.
One of the challenges in developing smaller air curtains is to completely block incoming aerosol particles over time, as it is difficult to maintain the air wall over a long distance.
The devices lose the intensity of the air discharge and create a turbulent flow that allows infected aerosol particles to escape into the surrounding environment.
To solve this problem, the DACS has a discharge and suction port, where the generator at the top produces the airflow which is guided to the suction port at the bottom which captures all the particles.
A high efficiency particulate filter (HEPA) can be installed in the suction port which purifies the air.
The researchers are also developing an addition to the device that would disinfect the air with ultraviolet light and recirculate it to maintain the air curtain and the air pressure in the room.
The DACS was tested using an air compressor connected to a mannequin to simulate breathing.
Dioctyl sebacate, a widely used solvent that spreads easily, was added to the airflow to create traceable aerosol particles.
Particle image velocimetry and high-speed cameras were used to measure the blocking effect of DACS.
They showed aerosol particles approaching the DACS before bending sharply towards the suction port, meaning the air curtain completely blocked all incoming aerosol particles.
When the researchers placed the manikin’s arm through the DACS to mimic blood collection, the airflow was interrupted, although the device was still able to block aerosol particles.
The researchers also tested the device on patients having blood drawn at Nagoya University Hospital in Nagoya, Japan.
They are now looking to lower the suction port so the arm can be placed under the heart for proper blood collection.
The results were published in the journal AIP Advances.
This story was provided to Newsweek by Zenger News.