TEXAS - Sirens Silent in Grand Prairie: System Failure Attributed to Human Errorgreenspun.com : LUSENET : Grassroots Information Coordination Center (GICC) : One Thread
[Fair use for education and research purpose only]
Updated: Thursday, Mar. 30, 2000 at 23:03 CST
Title: Sirens silent in Grand Prairie; System failure is attributed to human error
By Tawnell D. Hobbs Star-Telegram Staff Writer
GRAND PRAIRIE -- An error by a Grand Prairie dispatcher Tuesday night prevented the city's warning sirens from activating to alert residents of an approaching tornado, city officials said.
"There was a mistake made in the procedure, and the alarm did not activate," Mayor Charles England said yesterday. "It was a human error."
Police Chief Glen Hill said the city's complicated alarm system and a night that saw 165 phone calls from residents worried about the weather contributed to the mistake.
Hill said the error happened at 7:10 p.m., when the decision was made by a fire battalion chief to activate the warning system.
Grand Prairie's alarm system has a five-step process, which was not initiated in the appropriate sequence, causing the system to malfunction, Hill said.
England questioned whether the dispatcher was trained in using a complicated system.
"I think certainly we need some more training," he said.
Hill said he did not know if the dispatcher had ever activated the system because the procedure is tested during the day and she works at night. Hill said the department will have night dispatchers come in during the day to participate in testing the alarm system.
Grand Prairie's alarm system is activated the second Saturday of each month. The last activation was March 11. It showed that 11 sirens were functioning. Three other sirens were not working and have not been repaired.
The alarm system is activated by pushing buttons on two consoles, Hill said. Then the dispatcher selects a type of warning signal. The final step is pushing a transmitter button to send a signal to the sirens, activating them, Hill said.
Hill said after the system didn't activate, the dispatcher discovered that she had only activated one of the consoles. She repeated the steps, but because the process was out of sequence, the sirens did not sound, he said.
Hill said the system gave every indication that it was a successful transmission and the dispatcher was unaware that the system was not functioning.
"The indication was the system was activated, and in fact it did not," Hill said. "We believe there was a step left out. The dispatcher didn't know that it didn't activate. She believed that everything was done and a transmission had been sent out."
Hill described the dispatcher as conscientious, because she had called the battalion commander about the storm's severity before he called to recommend activating the system.
The tornado damaged as many as 56 homes in a subdivision just east of the Arlington city limits between Pioneer Parkway and Arkansas Lane. At least eight of the homes, mostly in the 2600 block of Parkside Drive, will have to be condemned, city officials said.
An official with the National Weather Service classified the tornado in the Grand Prairie area as an F2 on the Fujita scale, with winds of 113-157 mph. No injuries were reported as a result of the storm. A damage estimate was not available yesterday.
England said the alarm system should not be used in Grand Prairie because alarm systems give a false sense of security and are undependable. Radio and television stations are more dependable and have sophisticated equipment to track storms, he said.
"It's too cumbersome and too complex," Hill said of the system.
Hill said the process was put in place to prevent accidental activation, but the process will be refined.
"We want to make sure there is no room for error," Hill said. "I feel sorry that the system didn't activate. We were fortunate there was no loss."
Tawnell D. Hobbs, (817) 548-5487
) 2000 Star-Telegram, Fort Worth, Texas http://www.star-
-- (Dee360Degree@aol.com), March 31, 2000