Ref.: https://www.nytimes.com/2020/05/07/science/ultraviolet-light-coronavirus.html
[...] Some researchers hope a decades-old technology might get its moment and be deployed in stores, restaurants and schools.
[...] It has the ungainly name of upper-room ultraviolet germicidal irradiation, and it is something like bringing the power of sunlight indoors.
"We have struggled in the past to see this highly effective, very safe technology fully implemented for airborne infections," said Dr. Edward A. Nardell, a professor of global health and social medicine at Harvard Medical School. "We've done the studies. We know it works."
[...] Ultraviolet light mangles the genetic material in pathogens — DNA in bacteria and fungi, RNA in viruses — preventing them from reproducing. "You've killed it essentially," said William P. Bahnfleth, a professor of architectural engineering at Pennsylvania State University.
[...] Dr. Nardell estimated that installing commercially available fixtures for an intermediate-size warehouse-type store like Walmart would cost about $100,000, which might be too expensive for some smaller businesses.
The systems also add to electricity bills and require cleaning and maintenance. "They're not plug in and walk away forever," Dr. Nardell said.
[...] During five years of experiments at several schools there, students in classrooms outfitted with ultraviolet fixtures were less likely to catch and spread some contagious diseases, such as smallpox and mumps.
The most striking divergence occurred during the spring of 1941 when measles swept through schools around Philadelphia. At Germantown Friends School, one of the schools studied, ultraviolet fixtures had been installed in the primary grade classrooms. There, about 15 percent of children who did not possess immunity to measles — that is, those who had not previously contracted the disease — became sick.
In the upper-grade classrooms, where ultraviolet fixtures had not been installed, more than half of the susceptible students contracted measles.
[...] Some researchers hope a decades-old technology might get its moment and be deployed in stores, restaurants and schools.
[...] It has the ungainly name of upper-room ultraviolet germicidal irradiation, and it is something like bringing the power of sunlight indoors.
"We have struggled in the past to see this highly effective, very safe technology fully implemented for airborne infections," said Dr. Edward A. Nardell, a professor of global health and social medicine at Harvard Medical School. "We've done the studies. We know it works."
[...] Ultraviolet light mangles the genetic material in pathogens — DNA in bacteria and fungi, RNA in viruses — preventing them from reproducing. "You've killed it essentially," said William P. Bahnfleth, a professor of architectural engineering at Pennsylvania State University.
[...] Dr. Nardell estimated that installing commercially available fixtures for an intermediate-size warehouse-type store like Walmart would cost about $100,000, which might be too expensive for some smaller businesses.
The systems also add to electricity bills and require cleaning and maintenance. "They're not plug in and walk away forever," Dr. Nardell said.
[...] During five years of experiments at several schools there, students in classrooms outfitted with ultraviolet fixtures were less likely to catch and spread some contagious diseases, such as smallpox and mumps.
The most striking divergence occurred during the spring of 1941 when measles swept through schools around Philadelphia. At Germantown Friends School, one of the schools studied, ultraviolet fixtures had been installed in the primary grade classrooms. There, about 15 percent of children who did not possess immunity to measles — that is, those who had not previously contracted the disease — became sick.
In the upper-grade classrooms, where ultraviolet fixtures had not been installed, more than half of the susceptible students contracted measles.