At nearly every airport gate I have entered over the past two years, inevitably there has been an announcement that the flight is full, overhead space will run out, and the gate agents are looking for volunteers to check their baggage. The gate agents would then advise flyers to take keys, medications and valuables out of checked bags. They also would warn flyers to take spare lithium-ion batteries out of checked bags, but this announcement always seemed to get lost in the airport noise. However, it actually is a Federal Aviation Administration (FAA) regulation that spare lithium-ion batteries for consumer products must be removed from checked baggage and kept with the passenger in the aircraft cabin with the battery terminals protected from short circuit.

The FAA reports that one lithium-ion battery “incident” occurs every 10 days on airplanes and at airports. In November 2017, panic ensued at Orlando International Airport when a camera’s lithium-ion battery exploded at a security checkpoint, which caused a terminal to be evacuated. More recently, a portable power-pack charger in a carry-on bag went into thermal runaway in overhead storage on a China Southern Airlines flight during boarding, causing a small fire.

While in the airport, consumers are always looking for spare outlets to charge their lithium-ion battery powered devices – and open outlets are difficult to find. Luggage manufacturers filled this consumer-driven need by making “smart luggage” – baggage equipped with lithium-ion battery packs connected to charging ports in order to charge other devices. The major U.S. airlines, however, recently announced that “smart luggage” cannot be checked if the internal battery packs are non-removable.

The FAA also has promulgated regulations barring recalled consumer products containing lithium-ion batteries from commercial flights. The major concern surrounding these policies and regulations is to reduce the likelihood of a fire in an airplane. An uncontrolled fire occurring anywhere is an emergency situation; an uncontrolled fire occurring in a sealed aluminum tube traveling 500 miles per hour 7 miles above ground is a potential mass casualty event.

Fires in airplane cargo holds result in catastrophes – notably ValueJet Flight 592 in 1996. Since then, the FAA, airlines and airplane manufacturers have implemented policies and procedures and developed safety systems to reduce the likelihood of uncontrolled cargo hold fires. A fire in an airplane cargo hold is a much more difficult situation than one in the passenger compartment. In the passenger compartment, passengers and crew can use their senses to detect the early stages of a fire, actually assess the situation and respond accordingly to extinguish the fire. Pilots must rely on sensors to detect the early stages of a fire in a cargo hold, and must rely on fire suppression systems (if installed) to extinguish cargo hold fires, or perform maneuvers to starve the fire of oxygen, such as increasing altitude.

In 2010, a UPS cargo plane crashed in the United Arab Emirates because of a fire in the cargo hold. The fire is believed to have been caused by a shipment of lithium-ion batteries. Investigation revealed that the on-board smoke detection system took too long to activate and did not timely alert the two crew members, both of whom died. The fire disabled various systems on the plane, including the oxygen supply, and smoke filled the cockpit within three minutes of alarm activation. This scenario playing out on a commercial airliner is what the announcements, policies and regulations are trying to prevent.

As previously stressed, the likelihood of a battery failure is rare – and statistically, commercial airline travel is one of the safest means of travel when comparing deaths versus passenger miles traveled. Hundreds, if not thousands, of lithium-ion battery powered devices are on each commercial airline flight in things such as phones, tablets, computers, activity trackers, cameras and headphones. Consumers, however, must realize and respect the risks that are associated with these products if not used, stored or charged correctly. Battery manufacturers, and the manufacturers of products containing batteries, must be ready to respond to all claimed incidents.