A miniature air curtain has been developed to stop the spread of COVID-19 in hospitals and other health facilities where social distancing or wearing masks is not possible.
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 believe this system will be effective as an indirect barrier for use in blood testing labs, hospital wards and other situations where adequate physical distance cannot be maintained, such as at a reception desk.”
An air curtain or air door is a fan-driven ventilation system that creates an air seal over an entrance.
Hospitals use them to prevent ambulance fumes and other contaminants from reaching the inside of an emergency room.
One challenge 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 environment.
To address this, the DACS has a discharge and suction port, with the generator at the top producing the airflow that is routed to the suction port at the bottom which traps all particles.
A high-efficiency particulate air filter (HEPA) can be installed in the suction port to purify the air.
The researchers are also developing an addition to the device that would purify the air with ultraviolet light and recirculate it to maintain the air curtain and air pressure in the room.
The DACS has been tested using an air compressor connected to a mannequin to simulate breathing.
Dioctyl sebacate, a common solvent that disperses easily, was added to the air stream to create aerosol particles that could be traced.
Particle frame rate measurement and high-speed cameras were used to measure the blocking effect of the DACS.
They showed aerosol particles approaching the DACS before abruptly curving towards the suction port, meaning the air curtain completely blocked all incoming aerosol particles.
When the researchers put the mannequin’s arm through the DACS to mimic the blood draw, the airflow was disrupted, although the device was still able to block aerosol particles.
The researchers also tested the device on patients who had blood drawn at Nagoya University Hospital in Nagoya, Japan.
They are now looking at lowering the suction port so that the arm can be placed under the heart for proper blood draw.
The findings were published in the journal AIP Advances.
This story was provided to Newsweek by Zenger News.