Let's say that a major bridge in your city has collapsed at the height of rush hour, claiming an unknown number of victims. You'd like to communicate with your staff, both to ascertain their well-being and to tell them what to do tomorrow.

You could set up a call tree, and have every person call five other people until everyone was reached. Setting up one would be slow, and getting results would be even slower. Worse yet, the first thing that typically happens during local disasters is that the phone system is overwhelmed, making it difficult to reach anyone.

Or you could use an emergency notification service. Transmitting from multiple sites around the country, it will try to get your message to everyone on your list simultaneously, and will keep trying until it gets an answer from every person. Typically, it can be called on to try a variety of communications channels, in whatever order you specify.

Try everything, and keep trying

Channels mentioned by sources include office e-mail, home e-mail, home telephone, office telephone, office cell phone, home cell phone, text messaging, BlackBerry, fax, satellite phones, pagers, alternate phones at summer cottages and contacts for relatives who the employee might flee with during a hurricane.

The disaster scenario above became real at 6:05 p.m. on Wednesday, Aug. 1, when the I-35W eight-lane highway bridge over the Mississippi River in Minneapolis did collapse.

The Minneapolis office of Blue Cross and Blue Shield of Minnesota sent out 4,079 emergency notifications at 8:03 p.m. that evening, says Bob Niebuhr, a business continuity specialist at the insurance company. It was using a system from MessageOne. Located in Austin, it's one of about a half-dozen firms that offer emergency notification services.

"We were concerned that some of our people were on the road and could have been impacted," Niebuhr recalls. "We wanted to make sure they were OK, and if they were affected, we wanted to see if we could supply assistance. We also wanted to make sure we would be adequately staffed the next day. Third, we wanted to get information out to our employees as to what had happened."

The system first tried the recipients' work e-mail, because many employees have BlackBerries, Niebuhr says. If it didn't get through, it then tried the recipients' work cell phone, home telephone, personal cell phone, personal e-mail and finally an alternate home phone if available.

The message got through to all the recipients, mostly via e-mail. The first response came back within eight minutes, and after an hour, there was a 50 percent response rate. At that point, Blue Cross stopped sending out the notifications. Some responses came in the next day, and the total response rate was 68 percent, Niebuhr says.

Some of the recipients said it wasn't clear to them if and how they were supposed to respond, and some who called back to the corporate switchboard couldn't get through because they forgot their ID numbers. Also, the Caller ID of the notification call was an 866 number, leading some to assume it was a telemarketing call and they ignored it.

Although there had been internal publicity and training concerning the system, Niebuhr decided that more was needed, and his department has been mounting presentations since then, he says.

Also using the MessageOne system, the Minneapolis office of the international law firm of Fulbright & Jaworski got better results with a smaller group. It sent out a telephone message at 9:58 that evening to its 60 local staffers. The message asked the recipients to press one to indicate that they were OK, and other numbers to indicate problems, says Matt Ridings, disaster recovery administrator in the law firm's Austin office.

If the alert reached an answering machine, it left a different message, asking the recipient to call back via a toll-free number. Those who received the message in e-mail format could simply reply the same way.

"We had a 65 percent response in 10 minutes, and 78 percent within 35 minutes," he recalls. "By the end of the evening, there were only seven people we did not know about, and we knew about every employee by 9:52 the next morning. The staff was impressed by the fact that the firm was proactive enough to try to reach out to them."