Optus has told the communications regulator up to 470,000 Samsung devices connected to its network may not be able to call triple-zero.
In a Senate estimates hearing with the Australian Communications and Media Authority (ACMA) the figure was labelled as a "worst case scenario."
A further 114,000 Samsung phones connected to Telstra were also affected by the software issues that can inhibit emergency calls.
Optus and TPG announced in late October that there were issues impacting more than 70 models of Samsung devices.
Customers were told 11 models of devices would not be operable, while 60 Samsung devices needed a software update to remain compatible with the triple-zero network.
Telcos started sending out texts and emails to customers, however TPG Telecom, which owns Vodafone, reported a Sydney man died last month after a Samsung device was unable to dial triple-zero.
An estimated three people's deaths were connected to an Optus outage last month.
Liberal Senator Sarah Henderson asked ACMA chair and agency head Nerida O'Loughlin why more wasn't done to alert the community more than a year ago when the issue with devices was first flagged as part of the 3G shutdown.
Telstra and Optus completed their 3G network shutdowns in October last year. Vodafone's 3G network was shut down last January as telcos moved to make room for 4G and 5G technology.
O'Loughlin said: "The process was really around the networks knowing which devices wouldn't work, and the networks having that relationship with their customers ... because it only affected a subset of people using those networks."
The telcos gave customers with such devices between 28 and 35 days to upgrade their service or get new devices, otherwise they'd be blocked from the network.
In Senate estimates on Tuesday, AMCA officials said Telstra reported 114,527 devices on its network were affected and would be blocked between now and early January.
For Optus the number of devices affected is still in the process of being discovered, however officials said the "worst case scenario" was 470,000 devices.
ACMA investigations are still underway and will be made public once finished.
Share
