A review into the Optus Triple-Zero outage that was linked to two deaths in September has revealed widespread issues and an overall "lack of care" about mistakes that led to the incident.
The review examined the 14-hour failure that led to 605 people unable to connect to the emergency line in South Australia, Western Australia, the Northern Territory and part of NSW on September 18.
It found that Optus gave contractor, Nokia, incorrect instructions for a routine upgrade, which led to at least 10 crucial mistakes.
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Optus and Nokia were found to have been unaware of the issue for 13 hours, as the call centre failed to escalate reports from five callers that Triple Zero calls were not working.
The report found there were internal gaps, including poor information flow that failed to acknowledge the severity of the outage and siloed structures.
"The lack of care and work discipline evident in all the mistakes that were the cause of this incident is more difficult to address," the report said.
The other major issue was that the Triple Zero calls did not latch onto other networks as they should have, which the report stated was "puzzling".
"This raises issues about how well the Triple Zero system is operating and whether it can be improved," the report said.
The Optus review handed down 21 recommendations, including encouraging staff to escalate issues outside their immediate group, considering whether Optus should contract its complex and essential services, and shifting the siloed nature of work.
At a meeting earlier this week, the board accepted all the recommendations and agreed to implement them quickly.
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The board will also fine or fire the employees personally accountable for the failures.
Optus chairman John Arthur said the report was a "sobering read".
"We are deeply sorry for the 18 September outage that impacted Triple Zero services and the consequences for any Australians who were trying to reach emergency services," he said.
"We recognise the scale of the challenge and will act decisively to make the necessary changes to strengthen the business and rebuild trust."
Optus chief executive Stephen Rue said some of the key reforms needed were already under way, and the company will regularly report its progress.
"Our commitment is not just about compliance, it's about setting a new standard for our performance as a critical infrastructure provider of essential services and serving the community," he said.
"Australia deserves world-class emergency call services.
"We are working closely with government, regulators, and the wider telecommunications sector to enhance the reliability of the Triple Zero service for our customers."
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