UK network operator Openreach has told its customers to remove lithium batteries from its telephone exchanges due to potential fire concerns.

First reported by ISPreview, Openreach on Thursday announced it was giving its communication provider (CP) customers just 48 hours to remove any in-rack lithium batteries from BT exchanges.

In a briefing only accessible to Openreach customers, the company said the batteries were prohibited by the operator’s building safety policy “due to the significant risks … [of] thermal runaway, fire and explosion.”

“Openreach mandates the use of lead acid batteries as the preferred and safest option for battery backup in CPs’ colocation or Access Locate customer cabinets,” the briefing.

Some communication providers told ISPreview that they were uncertain where in Openreach’s documentation restrictions around battery chemistry types were expressed.

Openreach told DCD the company has found an extremely small number of cases and doesn’t believe the move will have a significant impact.

“Safety is our number one priority, so we pay close attention to best practice, expert research, and industry-recommended standards when it comes to fire safety,” an Openreach spokesperson said.

A "handful" of lithium batteries linked to some equipment owned by one CP were found during a recent annual maintenance check at one of the firm's exchanges.

This is "extremely unusual," according to Openreach. "The use of batteries is rare in itself and, any CPs that do, overwhelmingly use the safer lead/acid variety," the spokesperson continued: “We don’t believe this is a widespread issue which will impact any other CPs but, given the importance of safety in our buildings and wider estate, we felt it was the right thing to do to send out guidance on battery usage.”

Openreach, the wholesale infrastructure arm of UK telecoms firm BT, operates thousands of telephone exchanges across the UK. The company operates telecoms and fiber networks from these facilities, which in turn are resold by ISPs such as Sky, Vodafone, and BT. Many communications firms will house their own network equipment in these facilities.

BT and Openreach are in the midst of a major exchange exit program. As part of the companies’ shutdown of their copper network, some 4,600 exchanges are set to shut over the next decade, with around 1,000 retained to provide fiber services going forward. Openreach aims to close more than 100 legacy exchanges by December 2030.

DCD visited the BT Tower in London and spoke to Openreach about its exchange exit program in the latest issue of DCD>Magazine. Read it here for free.