US plane security turns on batteries

New rules from the US Transportation and Security Administration (TSA) that took effect in the US on 1 January ban travellers from carrying loose lithium batteries in checked baggage. Passengers are allowed to pack two spare batteries in their carry-on bag, as long as they are in clear plastic bags.

The TSA, however, has said it's safe to check in items such as a laptop or iPhone that already have the batteries in place.

The agency said loose lithium batteries not installed in devices pose a fire risk to passenger planes. Recently, the National Transportation Safety Board could not rule out the possibility lithium batteries started a fire in a plane at the Philadelphia National Airport last year, according to the Associated Press.

The batteries in carry-on luggage are also subject to certain rules. Batteries can only contain an equivalent of up to eight grams of lithium content. (Most batteries for mobile phones and laptops meet this requirement.) And for lithium metal batteries, whether carried as a spare or installed in a device, batteries are limited to two grams of lithium metal.

Desiree Everts writes for CNET News.com