UV lights kill virus at food plants
State-of-the-art system boosts safety for workers gathered in common areas
B.C.-based food manufacturer Nature's Path has installed cutting edge ultraviolet lighting and air disinfection filters at its plants that promise to rid indoor air of the virus that causes COVID-19.
All three plants — in Delta, Blaine, Wash. and Sussex, Wis. — have been equipped by Florida-based Healthe Inc.
Proprietary downlights for general illumination employ “FarUVC 222 nanometre light” to sanitize the air in break and lunch rooms where physical distancing is a challenge. They have also installed specialized “troffers” — ceiling-mounted circulators that draw air through carbon filters and treat it with the same wavelength of UV light.
The elements fit easily in existing fixtures and infrastructure.
“We have a lot of LED and fluorescent fixtures, and the neat thing that Healthe has done is make these systems so easy to retrofit,” said Barry Galbraith, the director of manufacturing for Nature's Path Foods. “It's so easy I think we got it done in just a couple of hours.”
The organic breakfast and snack manufacturer spent more than $1 million earlier this year on barriers and physical distancing equipment on the production floor. But because employees have to remove their masks to eat, management wanted a solution to keep them safe in common areas as well, said Galbraith.
“That's where these systems play a vital role cleaning the air and surfaces.”
UV light has long been used to destroy viruses, bacteria and other pathogens. For instance, Metro Vancouver employs UV disinfection at its Coquitlam and Seymour water-treatment plants.
The UV light wavelengths typically used in industrial settings are harmful to the skin and eyes. But a recent study published in Nature Scientific Reports revealed that Far-UVC light with wavelengths between 207 and 222 nanometres doesn't harm human tissue.
Earlier research found that FarUVC light effectively kills airborne influenza, and the latest tests revealed that the equipment is also effective against two versions of the coronavirus — viruses similar to SARS-CoV-2, which causes COVID-19.
“As all human coronaviruses have similar genomic sizes, far-UVC light would be expected to show similar inactivation efficiency against other human coronaviruses, including SARSCoV-2,” the Columbia University researchers wrote. “Low-dose-rate far-UVC exposure can potentially safely provide a major reduction in the ambient level of airborne coronaviruses in occupied public locations.”
Healthe lighting and filtration systems are used “anywhere where people cluster,” said Fred Maxik, the company's chief scientific officer. That includes schools, restaurants, offices and industrial spaces. In many cases, the systems are installed in areas that people share, but not necessarily the entire workplace, often at a cost of about US$10 per square foot.
A year ago, much of the Florida company's business was in circadian lighting, which restores the body's sleep and waking cycles, said Maxik, who has published some of the work he has done with NASA.
But the COVID-19 pandemic has dramatically grown the market for products designed to disinfect air, “so we've made a substantial pivot.”
The lighting systems consume up to 25-30 per cent more energy than typical commercial lighting, but timers and sensors help keep those additional costs closer to 10 per cent by turning the equipment off when the space isn't being used.
The air filtration systems are easily installed in areas with drop ceilings that are common in commercial spaces, while downlights will work where air filters aren't an option and over surfaces such as countertops.