The Bay of Plenty's tsunami sirens warning system is to get a "truer test" of its capabilities with a two-minute continuous burst at noon tomorrow.
Western Bay emergency management chief Barry Low said the longer blast will be a more accurate test to see whether the sirens can be heardfrom much further away than they were during the 10 to 15-second burst on May 18. It will also help identify any gaps in coverage.
On May 18, the sirens sounded at fire stations throughout the Western Bay of Plenty, yet many people along the coastline failed to hear them.
The region's mayors conceded the initial blast was insufficient.
Mr Low said Civil Defence personnel hoped tomorrow's test would be far more penetrating along the coastal strip but warned that even if the alarms were blaring for 10 minutes - as they would in a genuine emergency - there was no guarantee of blanket coverage.
He said people also must understand the tsunami warning sirens were only one element of the overall warning system, which included radio and television media coverage and word-of-mouth messages and also relied on people's own preparedness to act in any Civil Defence emergency.
There is no coverage at Te Puna and Matua, though there is a plan to install an additional siren in the area at a cost of $3000-$10,000, depending on whether a tower was also needed.
Mr Low said a helicopter-mounted alarm system to warn people in areas without siren coverage was being considered.
He said any Civil Defence emergency management plan had its limitations and self- reliance was a key aspect to it: "The point is that people need to take personal responsibility for themselves and their families and be prepared to be self-reliant in an emergency for at least three days.
"And it's vital people are prepared to act when the warning goes out."
The district health board is the lead agency to evacuate special-care residents and the frail and vulnerable from their homes, who would be traced through local community groups.
Tests of the Bay's tsunami warning system will take place every three months.
* Check out www.getthru.govt.nz for simple messages on what to do in a disaster.
