Ambulance blackout answers still sought

Tasmanian authorities remain unaware of what caused a blackout at Hobart's ambulance headquarters, shutting down its communications centre, and delaying the dispatch of paramedics to a terminally ill woman who died.

The communications were impacted for almost three hours on Sunday until 3.30am and Health Minister Michael Ferguson said independent operational and technical reviews will be undertaken.

"It's too early to be definitive about the exact causes, we've got early advice, but we're fact-checking all of those," he told reporters on Tuesday.