HONG KONG — Airline passengers should ensure their power banks are in good condition and from reputable brands before boarding flights, experts have warned, after a charging device was suspected to have caused a fire on board an aircraft preparing for departure from South Korea to Hong Kong.
Investigations are continuing into what sparked the fire that engulfed the Air Busan aircraft at Gimhae International Airport in the country's south on Tuesday, but local media reports suggest a power bank stowed in an overhead locker started it.
Authorities initially reported that three people were hurt but increased the number to seven on Wednesday. One person remained in hospital, the country's transport ministry said. A total of 169 passengers and seven flight attendants and staff were evacuated from the Airbus A321 using inflatable slides.
Lo Kok-keung, a retired engineering professor who provides expert witness testimony on traffic accidents, said on Thursday that passengers should check their power banks to ensure they were in good condition and avoid bringing old ones on board.
The internal insulator or wires inside older power banks could wear down over time, which could cause a short circuit, he said.
"If it creates a short circuit it can create a high temperature and burn the internal materials and create a fire … which can burn clothing in the baggage," he said.
Lo said the reaction could happen suddenly, leading a small fire to quickly become big.
To be safe, he suggested passengers keep power banks in their possession rather than stow them away. He also advised passengers to avoid using them during a flight.
It was also important to buy power banks from reputable brands, Lo added.
Warren Chim Wing-nin, deputy chairman of the Hong Kong Institution of Engineers' aircraft division, said passengers should cover all connection points on power banks when not in use to avoid short circuits.
But more of a concern, he said, was to ensure power banks were of good quality.
"If it is not a good product, of course, the risk will be much higher," he said.
Chim said that while power banks were supposed to undergo tests issued by the United Nations (UN), there was no accreditation or safety systems in place for airport security or cabin crew to distinguish between good and bad devices.
If passengers found power banks were producing "abnormal heat" or beginning to smoke, they should immediately tell the cabin crew, he added.
According to the International Air Transport Association, the trade body for airlines, power banks are considered "spare lithium batteries" and forbidden from checked luggage and instead must be carried on.
Carry-on power banks are still subject to some restrictions, however.
Under guidelines from the International Civil Aviation Organisation (ICAO), an agency under the United Nations (UN), shared by Hong Kong's Civil Aviation Department, lithium battery devices used as power sources, such as power banks, should not exceed a watt-hour (Wh) rating of 100.
They should also be individually protected to avoid short circuits, such as by placing them in their original retail packaging or by taping exposed terminals.
Hong Kong carriers such as Cathay Pacific Airways and HK Express allow passengers to take up to 20 spare batteries under 100Wh on board, while devices ranging from 100Wh to 160Wh are limited to two.
Emergencies on board passenger planes due to power banks catching fire are not an uncommon occurrence.
Last February, a flight from the Philippines to Shanghai was forced to make an emergency landing in Hong Kong after a passenger's power bank exploded while charging an iPad.
The iPad also reportedly caught fire after being disconnected from the device.
No one was injured during the incident.
Also that month, a power bank reportedly exploded on board a Thai AirAsia flight about 30 minutes after take-off from Bangkok. The aircraft made it to its destination on time after crew and passengers put out the fire.
In 2023, two passengers were injured after a power bank exploded shortly before take-off on board a Scoot Airlines flight from Singapore to Taipei.
The aircraft returned to its gate safely, but the owner of the power bank and another passenger reportedly sustained "minor burns" to their fingers.
