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Emergency Contact

Jurisdictions use reverse 911 systems to alert public of potential dangers.

Reverse 911 systems give public safety and law enforcement agencies a viable option for alerting the public in times of impending danger. Where a neighborhood previously might have heard of an escaped prisoner from a deputy at the front door, citizens and businesses now can be warned quickly and efficiently by phone with some simple technology.

A reverse 911 system allows an agency to pull up a map on a computer, define an area and send off a recorded phone message to each business or residence in that area. These applications vary by jurisdiction, but most use the technology to notify communities of chemical spills, missing persons, dangerous individuals on the loose or a string of crimes.

A missing 3-year-old Florida girl was found after a convenience store clerk, who had been alerted by a reverse 911 call, saw the girl as he was taking out the garbage behind the store. A couple of escaped prisoners in Maine were nabbed after a 3 a.m. reverse 911 call alerted a neighborhood about the escapees. One of the neighbors happened to look outside and saw a couple of individuals who turned out to be the escaped pair. In another case in Arlington, Va., police had run out of leads on a murder so they blanketed a two-mile area with a message soliciting information on the case. A tip came in and led to an arrest.

"It's pretty slick," said Frank Arnoldy, commander of support services for the Crestwood, Mo., Police Department. The department routinely uses reverse 911 to alert the public of criminal activity. The system also is used for less dire situations, such as parking issues. "Our public works department is in the process of a multi-year street reconstruction program and they've given people a timetable for not parking in a certain area. If they're off a notch they can alert them with reverse 911," he said.

The town of about 12,000 also uses it to check on elderly residents. "We call them once a day and they enter a four-digit number that signals they're OK," Arnoldy said. "If they don't respond, they'll send officers or emergency personnel."

A Flurry of Interest

Sigma Corp. started developing its system in 1993 and began placing it in communities about a year later, according to Jim Jones, sales manager of the corporation.

Sigma has placed about 200 of the systems around the country and has seen a flurry of interest recently. "We've probably, in the last 12 months, put in about 50 systems, so it has become a geometric progression," Jones said. "Certainly there's enough people using it now where people are aware of it, and certainly since Sept. 11, we've had a huge increase in the number of inquiries."

Sigma's system is a Windows 2000-based application. Sigma provides all the hardware, training and support. "If someone can operate a mouse and talk into a phone, they can use our system," Jones said.

The cost of a system depends on the number of outgoing phone lines needed to service an area, but begins at around $20,000. Brad Herron, general manager of the Hillsborough County Sheriff's Department said the Hillsborough system cost between $35,000 and $40,000. "Based on our population and the amount of information we want to get out, we chose 24 outgoing lines," he said. "A one-minute recorded message on our 24-line outgoing system will notify between 700 and 1,000 people an hour." Hillsborough's system is capable of notifying residents by more than just a home phone; pagers, cell phones and faxes also are used to transmit messages.

Cities and counties normally purchase the systems independent of each other but some combine or share systems, which gives them the capacity to alert a large number of people in the case of a catastrophic event.

Sigma begins installation in a jurisdiction by getting a database of names and telephone numbers of businesses and residences in the area. The company then programs those numbers into the computer system, delineating each by longitude and latitude so the numbers can be placed on an electronic map.

How it Works

To use the system, an operator records a message, brings up a map on a computer screen, designates a target area or chooses a preloaded map area, such as a flood-prone region, and hits enter. The system begins dialing all the numbers in the database within that targeted area, and sends the recorded message. An operator also can create an area around a center point, say a nuclear power plant, and program the system to call everyone within a mile of the plant.

System operators can create and save lists of individuals with common characteristics, such as a neighborhood crime watch group or emergency personnel, for future broadcasts. The system also can be programmed to leave a message on an answering machine or try the number again later.

In addition, the system can be set up to receive responses to its recorded message. "Suppose there's an evacuation," Jones said. "You're calling everybody in the flood plain saying, 'You need to run away, the water's rising. If you need help getting away, touch 7.'" The system automatically will print out a list of everybody who indicated they needed help, Jones said.

The system does have limitations because of the time it takes to get the messages out. "You can't use it for weather notifications because you'd have to have so many phone lines it would be cost prohibitive," Arnoldy said. "Generally, we'll use it the next day [following a crime] when the investigation has come up with some information. We'll send one out notifying residents of the burglary and any information we have."

A problem that crops up occasionally is the database of phone numbers is updated just once a year, but residents and businesses may move or change numbers before then. Residents can move out of a jurisdiction and keep the same phone number, which means that they may receive reverse 911 calls that aren't applicable to their location.

Another concern of operators of these systems is intrusiveness: Whom do you call and under what circumstances do you call? Sigma provides a commercial database for $6,000 that the firm purchases from the same companies that telemarketers use. The database includes only listed numbers. A recently passed federal law mandates that local telephone companies make available unlisted numbers for emergency use only.

Since some jurisdictions use the system for less serious matters than escaped convicts, they're careful about being too intrusive. Jurisdictions generally advertise the system in advance and inquire as to how the citizens want the system to be used.

Hillsborough County, Fla., officials sent out an initial 911 blitz that notified all businesses and residents with published numbers that the system was being implemented, and asked if each would like to participate. Everyone who received a reverse 911 call had the option of choosing to be included in future broadcasts or opting out by pressing a number.

"We had probably 400,000 homes and businesses to contact," said Herron, adding that the county supplied a phone number to call for anyone with an unlisted number who wanted to be a part of future broadcasts. "We entered thousands of non-published numbers into the system."

Some smaller jurisdictions use the system for public service announcements, such as notifying folks of a parking problem or even an upcoming Easter egg hunt. In those areas the citizens can choose to be notified for only specific occasions.

Jurisdictions don't have the authority to notify those with unlisted numbers unless there is an emergency. In that case, according to Jones, most jurisdictions will call everybody. "Because if there's a chemical cloud coming down the road and you don't call those people, they will sue you," he said.