A spokesman told APNZ they were trying to contact the about eight staff on the island.
Communication was usually through email or skype.
"We can't just pick up the phone and ring Raoul Island,'' he said.
Staff on the island were used to quakes, he said.
"There have been some other big ones this year but no damage,'' the spokesman said.
The Pacific Tsunami Warning Centre (PTWC) issued a Tsunami Information Bulletin in response to the earthquake.
While it initially said a tsunami was possible, sea level gauges on Rauol Island registered wave heights between 0.1 and 0.17m.
The New Zealand Tsunami Experts Panel convened and advised that there was no threat to New Zealand from this event.
There is not expected to be any impact on the Rena clean-up efforts.
Normal beach activities may continue, but there may still be some abnormally strong currents in some locations in the north of New Zealand. Caution is advised for swimmers, divers and recreational boat users.
Raoul Island is the largest and northernmost of the main Kermadec Islands, about 1100 kilometres north-east of New Zealand's North Island.
- HERALD ONLINE