Fire alert system serves NZ towers

By ELEANOR BLACK and AGENCIES

New Zealand buildings use the same type of automated fire alert system that told terrified World Trade Center office workers to stay at their desks after two airliners smashed into the towers.

Speculation is rife that thousands of people died because they trusted in computerised loudspeaker messages on September 11 and did not walk down the stairs to safety.

While building wardens and firefighters had the power to override the messages, for some reason they did not.

New Zealand's own high-rise evacuation procedures are modelled on those overseas and an Australian automated alarm system, similar to that used at the World Trade Center, has been adopted by 15 or 20 of Auckland's tallest buildings and several in Wellington.

The Emergency Warning and Intercommunication System (EWIS) is meant to prevent panicked people clogging stairways in the case of fire.

Auckland fire safety officer Gavin Parish said that in most situations it worked extremely well.

If fire breaks out on the floor of a high-rise, workers on the two floors above and the one beneath will receive a message to evacuate. All others will hear a warning tone.

Although the wording varies, the suggested message for evacuation, preceded by an alarm, is: "Evacuate the building using the nearest fire exit."

The standard alert message for people on unaffected floors is: "The fire alarm has operated. Stand by for further instructions."

Another message commonly used in Australia but not favoured here is eerily similar to survivors' reports of the World Trade Center message: "Please remain seated until you receive further instructions."

John MacGregor, of the Building Industry Authority, said that while the fire alarm computers in New York had worked as they were meant to, the system did not allow everyone to evacuate because it relied on human judgment.

"What you're dealing with here is expertise and judgment in relation to that structure.

"You would have needed the appreciation of a structural engineer on the spot.

"In all these things you have to leave room for human beings to make appropriate decisions on the day."

Given a clear walk, it would take a minimum of 28 minutes to descend the 110 floors of the World Trade Center.

This estimate does not factor in rest stops or delays due to the mass of people who would head for the stairs in an emergency.

Although survivors have commented on the calm that prevailed, thousands of people were squeezed into the narrow stairwells, pushing to get past dozens of firefighters on their way up to the fire.

Some survivors who worked above the 50th floor spent more that 45 minutes walking down to safety. The first tower collapsed within 60 minutes of being hit.

Robert Knowles, who worked on the 54th floor of the first tower hit, said progress down the stairs was good until he reached the 30th floor, where thick smoke obscured vision and water from the sprinkler system made the stairs slippery.

"It was really tough. I was praying for people in wheelchairs."

Blind computer worker Omar Eduardo Riviera made his way down from the 71st floor with the help of his guide dog.

"At first there was panic and some people tried to run and go first. But really ... most people grasped what was happening so we walked down in an orderly fashion, but it was slow going."

Full coverage: Terror in America

Pictures: Day 1 | Day 2 | Brooklyn Bridge live webcam

Video

The fatal flights

Emergency telephone numbers:

United Airlines: 0168 1800 932 8555

American Airlines: 0168 1800 245 0999

NZ Ministry of Foreign Affairs and Trade: 0800 872 111

US Embassy in Wellington (recorded info): 04 472 2068