BT has been fined £17.5m for a “catastrophic failure” of its emergency call handling service which led to thousands of 999 calls not being connected.
The network fault, which lasted for more than 10 hours on 25 June last year, led to 14,000 calls to emergency services failing to connect.
Following an investigation into the company which manages the 999 phone system, the regulator Ofcom said that BT was “ill-prepared” to respond to the problem.
“BT fell woefully short of its responsibilities,” said Suzanne Cater, Ofcom’s director of enforcement.
“Being able to contact the emergency services can mean the difference between life and death, so in the event of any disruption to their networks, providers must be ready to respond quickly and effectively,” she added.
BT also provides text relay services for deaf and speech-impaired people but the outage meant that these users were “unable to make any calls, including to friends, family, businesses and services”.
“This left deaf and speech-impaired users at increased risk of harm,” said Ofcom.
The telecoms watchdog said the emergency call handling system’s outage was caused by an error in a file on a server, which meant systems restarted as soon as call handlers received a call.
It led to staff being left staff logged out and calls being disconnected or being dropped as they were transferred to the emergency services.
An attempt to recover from the problem then failed, Ofcom said, due to a human error because instructions on how to solve such an issue were “poorly documented”.
The company apologised for the incident last year.
But an investigation discovered that the company’s preparedness for this kind of situation was “inadequate”.
“We found that BT did not have sufficient warning systems in place for when this kind of incident occurs, nor did it have adequate procedures for promptly assessing the severity, impact and likely cause of any such incident or for identifying mitigating actions,” Ofcom said.
The regulator added while the disruption was widespread, there had been no confirmed reports by emergency services of “serious harm” as a result, but warned “the potential degree of harm was extremely significant”.
BT has been contacted for comment.