The outage caused a series of problems at the Ambulance Tasmania communications headquarters for about three hours on Sunday morning, including a 35-minute period in which calls were received but all other IT systems were down.

Details of emergency calls had to be relayed to the adjacent Tasmanian Fire Service head office so ambulances could be dispatched.

During the disruption, two calls were received, one of which was a terminally ill woman who suffered a fatal cardiac arrest.

Ambulance Tasmania chief executive Dominic Morgan said information suggested the woman could not have been resuscitated.

‘‘Unfortunately, the patient was already terminally ill and receiving palliative care at home, and unfortunately passed away,’’ he said. ‘‘I think it’s important to just clarify that we believe at this stage that this is a patient that succumbed to her condition, which was a normal and expected passing for this person.’’

Mr Morgan pledged a full investigation into what had gone wrong.

‘‘Electrical systems are difficult and challenging things to ensure that there’s never a single point of failure,’’ he said.

‘‘But the community has to have confidence that people like myself take this very, very seriously and that we’re right behind getting to the point where we’re absolutely minimising the chances of this sort of thing occurring.’’

The investigation will be aided by the NSW Ambulance Service, which recently suffered a similar outage.

The Melville Street facility, which opened in 2010, cost $5.6million to build, including $1million on information technology systems.