The transport ministry said Tuesday that tighter portable charger restrictions on flights will be introduced on April 24, following a string of incidents involving such devices.
Under the new rules, each passenger will be allowed to bring no more than two power banks in their carry-on baggage, each with a capacity of 160 watt-hours or less.
Charging the batteries and using them to charge electronic devices such as smartphones during flights will be prohibited.
Other existing rules will remain in force. Portable chargers must be carried on board rather than being placed in checked baggage, and passengers are required to keep them within reach instead of placing them in overhead compartments or other storage areas.
Those charging portable batteries and bringing more than two chargers on board in violation of the new rules could face a prison term of up to two years or a fine of up to ?1 million.
There have been a series of incidents involving portable chargers on planes in Japan and overseas, such as catching fire and emitting smoke.
The tighter domestic regulations follow the adoption late last month of new international standards by the International Civil Aviation Organization, a specialized U.N. agency that sets global aviation rules.
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