By TravelandLeisure.com/Cailey Rizzo
Oct 14, 2018 @ 11:30 am

On Sept. 26, a man traveling in business class on Qantas Airways dropped his phone in his seat. The flight was about two hours from landing in Melbourne, Australia.

While he was trying to fish the phone out from his seat, it got crushed and began smoldering, smelling like burning rubber. Flight crew considered making an emergency diversion to Sydney, but before the situation escalated flight attendants used fire extinguishers to put out the flames.

The flight landed in Melbourne without any further problems, but the incident highlights an important safety issue not many passengers consider.

In safety announcements, airlines now advise passengers to alert a flight attendant if they lose their phone in the seat. While some may believe the precaution is so passengers don’t mess up the reclining mechanisms built into the seat, it’s actually a fire safety issue.

Lithium batteries can quickly overheat and, if damaged, can start a fire. According to the Federal Aviation Administration (FAA), there were 46 lithium-ion battery fires on flights around the world in 2017.

If you lose your phone in your seat during a flight, alert a flight attendant immediately. If the phone starts a fire or overheats, they are equipped to extinguish the flames. A flight attendant may take your overheating phone and submerge it in liquid or lock it in a fireproof box until landing.

If you’re packing spare batteries in your carry-on, keep them “protected from short circuiting with terminal caps or tape and never pocketed where they could come into contact with change, keys and other conductors,” says Aviation Week.

And one final note of warning: don’t pack spare lithium-ion batteries in your checked luggage. The FAA has banned lithium batteries from flying as passenger cargo and airlines will only allow them in carry-on luggage.

This article originally appeared on Travel and Leisure. For more stories like this, visit travelandleisure.com.