After watching a steady parade of people emerge from the lavatory on an extended commercial flight, many passengers are reluctant to expose themselves to the germs left behind.

But what if the lavatory could clean itself after every use?

Boeing engineers and designers have built a prototype lavatory that uses ultraviolet (UV) light to kill 99.99 percent of pathogens, thus sanitizing all the lavatory surfaces. Combined with touchless faucets, soap dispensers and more, the lavatory of the future could make for a more hygienic, less worrisome experience.

Engineers in Commercial Airplanes Product Development and Boeing Research & Technology (BR&T) are working on the lavatory and other concepts that would make the overall cabin cleaner. Principal investigator Teresa King from Product Development and her cross-functional team have shown through testing on their prototype that these innovations can minimize the growth and potential transmission of disease-causing microorganisms. Boeing has filed for a patent on this concept.

The lavatory uses far UV light, which is different from the ultraviolet A or ultraviolet B light used in tanning beds or grow lights, so it’s not harmful to humans. It is harmful to bacteria and pathogens and kills those organisms that are left on the surfaces of the lavatory.

“The UV light destroys all known microbes by literally making them explode,” said Jamie Childress, Associate Technical Fellow and a BR&T engineer. “It matches the resonant frequency of the molecular bonds on the outside of the microbes.”

“We believe that using the far UV is the key to making those surfaces cleaner,” King said. “We position the lights throughout the lavatory so that it floods the touch surfaces like the toilet seat, sink, countertops, etc. with the UV light. This sanitizing even eliminates odors from bacteria so that passengers can have a more pleasant experience.”

The UV lights could clean the lavatory during flight when the door is closed and the lavatory is unoccupied to minimize human exposure to the light as an extra precaution. The cleaning system even lifts and closes the toilet seat by itself so that all surfaces are exposed. The cleaning cycle takes less than three seconds.

The team’s design also incorporates hands-free faucets, a soap dispenser, trash flap, the toilet lid and seat, as well as a hand dryer to reduce the waste of paper towels. The team also is studying a hands-free door latch and a vacuum-vent system for the floor, all to keep the lavatory as hygienic as possible between scheduled cleanings.

“Some of the touchless features are in use on our airplanes today,” King said. “But we feel these, combined with the UV sanitizing, will make for a great clean package that passengers and airlines will love.”

Boeing’s Clean Lavatory concept is on the short list for being a Crystal Cabin Award finalist. The international Crystal Cabin Awards honor innovative cabin designs and ideas in seven categories. If Boeing's concept is one of the top three finalists in its category, the company will be presented the award on April 5 in Hamburg, Germany.

By Bret Jensen and Jordan Longacre