Before we had planes we had boats, and before germs, well, we still had germs

When we consider the fact that most commercial planes hold up to 350 passengers, it seems inevitable that dirt and grime will find their way onboard. Rapid layovers, high-pressure schedules, and constant boarding and deplaning of passengers mean that cleaning isn’t always the first priority for major airlines. While that isn’t exactly a revelation, it’s often something that fliers choose to sweep under the rug. Sure, there might not be an obvious flaming tire-fire or a wafting stench of dirty diapers, but under a microscope, some areas of airplanes are—to put it nicely—alarmingly disgusting and should be avoided at all costs.

10 Seatback Trays

If we had to take a stab in the dark and guess what the dirtiest spot on a plane might be, most people would assume it’s somewhere in the lavatory. We wouldn’t fault them for that assumption either, because really, it makes a lot of sense. Without getting into too many gruesome details that would spoil our appetite, we all know how nasty we can get in the bathroom.

Here’s the catch: airline staff are aware of this as a high-traffic area of germs and therefore make a conscious effort to always keep the lavatories as squeaky clean as possible. One area which receives minimal attention in comparison is the seatback tray table (you know, the one that you put your food on!). A study by TravelMath indicates that these tray tables carry eight times more germs than the toilet flush levers.

9 Air Vents

As humans, we’re all different. We each have our own preferences for food, lifestyle, travel destination, and music. Some of us sleep with a fan on while others need utter and complete silence. Where are we going with this? Well, we also all have pretty picky individual preferences for air conditioning. Compared to the lavatories, gross contact with the air vents is minimal. Therefore, cleaning becomes minimal too.

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We don’t know which rib-eating, finger-licking, nose-picking, butt-scratching person sat in our seat before us and fiddled around with the overhead vent. For those reasons, they’re pretty darn gross and might be worth a sanitizing wipedown before contact is made.

8 Seat Belt Buckles

There are some places onboard that, if we are aware of beforehand, we can make a conscious effort to avoid. One thing that we can’t avoid, however, despite our best efforts, is the seatbelt. Unfortunately (well, fortunately, we’d argue) every single passenger is required by aviation law to wear their seat belt during take-off, landing, and at the discretion of the pilot.

Sure, it might not be the filthiest spot on board the aircraft (yeah, we’re hinting at you, Mr. Tray Table), but hundreds of people have fondled it before you and hundreds will do the same once you’ve deplaned.

7 Headrests

Yeah, you know that place that you lean your skull against for the majority of the flight? Falling asleep open-mouthed and slowly drooling onto a recycled blanket, while wearing a deplorable $2 eye mask has happened to nine out of 10 of us over the years.

The aisle seat headrests are the zones we should be particularly wary of, because not only do they come into contact with our faces and hair (did someone say head lice?), but also the thousands of hands that walk up and down the aisle relying on them for balance. Again, we have no idea who washes their hands and who doesn't, and as a ‘low-germ zone,’ the headrests don’t get a whole lot of love in terms of cleaning.

6 Blankets

Sure, airline-provided blankets might be convenient, keeping us marginally warmer and a little more comfortable, but they’re also incredibly light and thin, and often are wildly too small. This means that you’ll still have to don an oversized hoodie and some wooly socks to keep warm. They can be pretty darn scratchy, too.

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All combined, that’s not too bad, right? Oh, did we forget to mention that your blanket has ALREADY BEEN USED BY COUNTLESS OTHER PASSENGERS? Yeah, we thought that would do the trick. As a rule of thumb, don’t use any airline blanket unless you physically unwrap it from the plastic (meaning it’s been washed). It’s still worth bringing a warmer one, regardless.

5 Seatback Pocket

From chewed-off fingernail clippings to banana peels, sugary crumbs, mushy baby food, and snotty, used tissues, the seatback pocket has the potential to deliver a germy surprise to any who dares reach for an in-flight magazine.

In times of rapid layovers and quick passenger changes, our good old seatback-pocket friends are often forgotten about entirely when it comes to a thorough (or even basic) wipe down. People have found all kinds of sticky, crumby, wet, pointy and gooey objects in there, and while it might seem like overkill, it isn’t entirely unheard of for people to bring a pair of disposable gloves.

4 Lavatory Flush Buttons

This one was simply inevitable. While the lavatories undergo a thorough cleaning and an overnight disinfecting after long-haul flights (according to the Wall Street Journal), that doesn’t mean that they’re kept spotless while in the air.

A one-way trip from Los Angeles, California to Melbourne, Australia takes approximately 15 hours (depending on headwind or tailwind), and during that time, we all need to use the potty a handful of times. Unless there’s a major “clean-up in aisle one!” moment, then aside from restocking toilet paper and tissues, cabin crew don’t spend much time of lavatory maintenance. But would we even want them to, considering that they’re the ones that handle our food as well?

3 The Touchscreens

Since the Golden Age of flying, things have gone a full 180 degrees. Legroom luxury has become a thing of the past, smoking on planes is now punishable by law, and sweatpants and a baggy hoodie is the new wave jet-tuxedo.

Entertainment and technology have changed remarkably too, of course, with endless films, TV shows, music and games available literally at our fingertips on a touchscreen device. But what do we do with a touchscreen? We TOUCH it! With our grimy, sweaty, sticky, germy, hands. And then someone else does, and then their nose-picking child swipes through the Disney films, and then the sick teenager who doesn’t wash his hands flicks through raunchy comedy films. You get the point - they’re not clean.

2 Tap Water, Tea, and Coffee

You’ve just woken up from a lousy three-hour on-and-off nap to the joy of a coffee and tea trolley slowly moving toward you in the aisle. A quick cup’a Joe might give you the kick you need to fend off potential jetlag, but you’d be thrusting germs into your body at the same time.

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Why? Because the in-flight tap water (which is used to brew tea and coffee) runs through a series of tanks and pipes that are cleaned rarely and sporadically. That’s why it’s always a good idea to bring your own bottle of water in case the cabin crew run out and need to switch to their tap water.

1 Lavatory Door Latches

When all is said and done and we’ve finished our private business in the lavatory, it’s time to flush, wash our hands, and head back to our cramped, germ-ridden aisle seat.

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Washing our hands in the lavatory isn’t as easy as it first sounds, however, with the sink’s automatic water shut-off forcing toilet-goers to into a “that’ll do” moment. The minuscule size of the sink itself means that large-handed folks struggle to even fit their entire fists under the tap. So, with half-clean hands, passengers slide the latch to exit the lavatory. Even if you make an effort to thoroughly scour your hands with soap, the majority of other passengers before you didn’t. Germs galore!