United has begun applying a new antimicrobial coating, which it says is long-lasting, to more than 30 aircraft based at Chicago O'Hare.
Use of the product, called Zoono Microbe Shield, augments the company's existing daily electrostatic spraying.
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Applications of Zoono are done weekly. The carrier said it will extend usage of the product to its entire fleet by the end of the year.
United says Zoono works by bonding to surfaces. It then creates a protective layer, resembling microscopic pins, that ruptures cell walls and membranes when microbes come in contact with it.
"This long-lasting, antimicrobial spray adds an extra level of protection on our aircraft to help better protect our employees and customers," Toby Enqvist, United's chief customer officer, said in a prepared statement
The product is EPA-registered. However, it hasn't been approved by the agency for use against all microscopic organisms. The product is currently registered as effective to use against mold, mildew and algae, the EPA said.
United's announcement about Zoono follows by a few weeks American's announcement that it will begin using a long-lasting antiviral surface protectant called SurfaceWise2 in the coming months. The surface coating works against coronaviruses for up to a week, American said. The EPA approved SurfaceWise 2, but only for use in Texas, under an Aug. 24 emergency order.