Airline reveals important reason pilots must be clean-shaven

Safety is important when you take to the skies - so much so it has to impact the bathroom routines of airline pilots. There is a good reason most pilots are clean-shaven - they have to be.

Airlines have disclosed that pilots are required to shave their beards to ensure the effective functioning of a crucial safety feature. While there is no Federal Aviation Administration (FAA) policy mandating pilots to shave, many do for safety reasons.

To guarantee a "snugly" fit for oxygen masks, several airlines have implemented policies requiring crew members to have either no or minimal facial hair. American Airlines and others have adapted their policies based on an FAA study titled "The Influence of Beards on Oxygen Mask Efficiency" published in 1987.

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The study stated that "Bearded crewmembers should be aware that oxygen mask efficiency is reduced by the presence of facial hair". Some airlines have specific rules regarding a pilot's facial hair.

For instance, Delta Air Lines permits sideburns but they can't extend below the middle of the ear. Pilots can also have a moustache, but it must be kept neat and not extend past the corners of the mouth.

However, beards are strictly prohibited according to Delta's rules, which don't even allow a few facial hairs covering part of your chin or cheek. A Delta spokesperson told Thrillist that the airline's facial hair policy originates from "the need for an oxygen mask to maintain a good seal in the event of an emergency".

Similarly, American Airlines requires pilots to be clean-shaven for the same reason. "We do not allow pilots with facial hair to be on active duty," said an American Airlines spokesperson.

It has been reported that a few airlines do permit their pilots to sport beards while on duty.

Hawaiian Airlines is one of those, and they do not require its pilots to be clean-shaven, according to multiple aviation forums.

It comes after an aviation expert revealed the best time to book flights for the busy summer holidays.

And this airline expert shared the common mistakes passengers make when an in-flight emergency hits - and they could cost you your life.