Dressing for a long flight can be challenging. You want to be comfortable, ensure that your outfit isn’t too warm or too cold, and maybe even look stylish. However, experts have weighed in on what to wear and, more importantly, what not to wear while flying. One surprising piece of advice? Avoid wearing leggings on a plane.

There has been plenty of advice over the years regarding proper airplane attire. Many flight attendants have shared their own recommendations about what passengers should wear to stay comfortable and safe. One common piece of advice is to avoid wearing Crocs or flip-flops, especially if you plan on using the restroom mid-flight.

“Be cautious about wearing sandals if you intend to use the lavatory,” one flight attendant warned. “That isn’t water on the floor (yes, use your imagination), and sandals allow whatever that liquid is to splash onto your feet.”

Another airline steward has cautioned against wearing shorts on a flight. In a viral TikTok video, he explained: “Try not to wear shorts when you’re on an airplane. It’s the same issue as touching the window—you never know how clean it actually is. If you wear pants, you’ll have less contact with germs.”

Now, an aviation expert has stepped forward to warn travelers against wearing leggings on planes.

The Hidden Danger of Leggings on Flights

Christine Negroni, a well-known aviation journalist and New York Times bestselling author of The Crash Detectives: Investigating the World’s Most Mysterious Air Disasters, has highlighted the risks of certain clothing choices on a plane. In an interview with IGV, she shared key insights into what passengers should and shouldn’t wear when flying.

Negroni advises wearing “comfortable flats with a substantial sole that are easy to remove.” She explains that in the event of an emergency evacuation, the ground outside the aircraft may be covered in hazardous conditions—cold, wet, icy, hot, or littered with metal, fuel, and debris from the airplane. Choosing sturdy shoes ensures that passengers can quickly and safely exit the aircraft without injuring themselves.

She also strongly advises against wearing high heels on a flight. Not only are they uncomfortable for long periods, but they can also be dangerous in an emergency. “If you are using the emergency evacuation slide, you’ll have to remove high-heeled shoes as they could puncture the slide,” Negroni states. “This is why flats are the best shoe choice.”

While the Federal Aviation Administration (FAA) does not have explicit rules about in-flight footwear, Negroni stresses the importance of keeping shoes on for takeoff and landing. These are the most critical phases of a flight when emergencies are most likely to occur.

Why Leggings Can Be Dangerous

In addition to her footwear recommendations, Negroni warns that leggings could pose serious risks during an in-flight emergency. While many travelers opt for leggings due to their comfort, she explains that the material they’re made from could be life-threatening in certain situations.

“Most air accidents are survivable, but many also involve fire,” Negroni told IGV. “Leggings are made from synthetic materials, which means that when these chemically produced fibers get hot, they melt and can bond to the skin.”

This can result in severe burns and long-term scarring, making survival even more painful and difficult. She references a 1999 FAA study, which concluded that natural fabrics such as cotton, wool, and leather provide better protection than synthetic materials like polyester or nylon. Even denim, though not always the most comfortable choice, is a better alternative to synthetic leggings in terms of safety.

Smart Dressing Choices for a Safe Flight

Considering these potential dangers, Negroni urges travelers to think carefully about their travel outfits. While comfort is important, safety should always be the top priority. By choosing natural fibers over synthetics and opting for sturdy, closed-toe shoes instead of flimsy footwear, passengers can significantly improve their chances of staying safe in an emergency.

Simple changes in what you wear during a flight can make a significant difference in your safety and comfort. Next time you prepare for a flight, consider opting for breathable, natural fabric clothing and a pair of solid, comfortable shoes. A small change in wardrobe choices can mean the difference between a smooth, worry-free trip and a potentially dangerous situation.