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Airports are teeming with germs, but not in the areas that you might think. While most people avoid the bathrooms at all costs due to the sticky floors and smelly toilets, they’re not actually the dirtiest place in an airport. In fact, if you were to guess the germiest thing at the airport, it probably wouldn’t be in your top three responses.

To find out the truth about the dirtiest places in an airport, InsuranceQuotes.com, a Texas-based insurance website, had researchers conduct 18 tests across six different surfaces at three major U.S. airports and airline flights. They used swab kits to identify the spots with the highest average amount of bacteria and fungal cells per square inch (CFU).

The results? The dirtiest place in an airport is actually the self check-in kiosk, which contained an average of 253,857 CFU, far above the runner ups. (One specific self check-in kiosk was even found with over 1 million CFU!) Coming in second for the dirtiest place in the airport are the airline gate bench armrests, which contained a little over 21,000 CFU. Water fountain buttons took third place with just over 19,000 CFU. Here are more secrets airports don’t want you to know.

Researchers also took a look at the germiest spots on an actual airplane, and, while airplanes contain slightly fewer germs than an airport, they too are filled with bacteria and fungal cells. According to the study, the plane bathroom’s flush button is the dirtiest, with an average of 95,145 CFU. The tray table and seat belt buckle follow far behind with 11,595 and 1,116 CFU. If you want to stay germ-free for the entire flight, you definitely shouldn’t do these 18 things on airplanes either.

Of course, when you think about it, none of these dirty spots should really come as a shock, considering the self check-in kiosk and tray tables are all probably the most touched items at an airport and on an airplane. But to put things in perspective airports and airplanes are a lot dirtier than say, an airport’s toilet seat, which contains 172 CFU, or a kitchen countertop with 361 CFU.

So next time you fly, wash your hands and use a hand sanitizer. Make sure you also stop making these 16 other airport mistakes before your next flight.