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Melissa Locker
August 28, 2017

Airplanes are a modern wonder that can fly you across the country or around the world in just a few hours. They are dazzling feats of engineering that have revolutionized travel and made the world a more connected place. Planes are incredible, but they are not exactly known for their cleanliness. In case you had any doubt about that, a new study shows that airports and airplanes are dirtier than your home—and some of the dirtiest spots are practically unavoidable.

A new study from Travel Math looks at the dirtiest places on the plane and the dirtiest spot is where your food is supposed to go. The study took four flights, surreptitiously swabbing them for germs and sending them to a lab. The results are an average from those four flights. The tray table was the dirtiest of all the locations and surfaces tested with 2,155 colony-forming units (CFU) of bacteria per square inch. A very distant second was the overhead air vent with 285 CFU per square inch, followed by the flush button in the lavatory (265 CFU square inch) and the seatbelt buckle (230 CFU per square inch).

The study also looked at airports and found that the push button on water fountains harbored a lot of bacteria—1,240 CFU per square inch.

While those numbers are alarming, keep in mind that most of us are exposed to a lot more germs during the day, especially if we’re pet owners. Travel Math looked at pet toys and dog bowls as well, and the numbers are jaw dropping. Pet toys had 19,000 CFU per square inch, while pet bowls had a whopping 306,000 CFU per square inch. Don’t let those numbers scare you, though: despite the frequent exposure to germs, pet owners are generally healthier than non-pet owners.

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Travel Math’s study, as well as new research shows that the very way that we board planes can spread disease, can make it feel like you’re stepping into a germ-filled flying sardine can. Luckily, it is fairly easy to limit your exposure to germs when you fly, as long as you plan ahead. First, bring some germ-fighting wet wipes from home or pick some up at the airport (Real Simple recommends Lysol Dual Action Wipes) and wipe down your tray table when you get onboard. While you’re at it, give the seat belt, the arm rests, the air vent, and the TV screen a wipe down, too. Then, before you eat or after a trip to the airplane’s lavatory, even if you washed your hands in the bathroom, use a hand sanitizer like Purell to make sure your hands haven’t picked anything up on the plane.