(NEXSTAR) – Southwest Airlines this week announced a new policy prohibiting the use of portable charging devices in overhead bins or closed carry-on bags.

The policy, which goes into effect later this month, was announced in response to a spate of incidents involving excessive heat, smoke or fire caused by lithium battery chargers.

“Southwest will introduce a first-in-industry Safety policy on May 28 requiring Customers to keep portable charging devices visible while in use during flight,” a spokesperson for the airline wrote in a statement shared with Nexstar. “Using portable charging devices while stored in a bag or overhead bin will no longer be permitted.”

Portable charging devices are already banned from checked bags by the Federal Aviation Administration for safety reasons. These devices — along with power banks, external batteries and all types of lithium batteries — are considered........

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