Why airplanes still have ashtrays in the bathroom

On a recent flight from Dallas to New York, I noticed that the airplane bathroom was equipped with several "no smoking" signs - as well as a convenient ashtray. My first thought was that I was on a really old plane since smoking has been banned from US domestic flights since 1990.

Curious, I asked a flight attendant about the ashtrays I'd seen.

Amanda Macias/Business InsiderSeveral 'no smoking' signs and then an ashtray in an airplane."If somebody did decide to light up and then put their cigarette in the trash, well, the trash is all paper products so the ashes could start a fire," Debbie an American Airlines flight attendant told me.

Turns out that all airlines are required by the Federal Aviation Administration (FAA) to attach an ashtray to the bathroom door of every plane.

The FAA categorizes bathroom ashtrays as part of each plane's "minimum equipment," meaning that a broken ashtray must be reported and replaced within 3 days.

In 1973, 123 passengers died on Varig Flight 820 traveling from Rio de Janeiro to Paris when the cabin of a Boeing 707 filled with smoke from a fire started by a cigarette.

The cigarette was thrown away in the the trash receptacle of the airplane bathroom causing a major fire in the rear of the jet.

Forty-two years after the Varig Flight 820 tragedy, here is another reminder of not to dispose of cigarettes in the trash receptacle.

Amanda Macias/Business InsiderA trash receptacle inside a plane bathroom.