Abstract: Guiding people toward an exit of a facility includes sending messages to a plurality of sounder devices, each message addressed to a corresponding one of the sounder devices and including a payload that specifies one or more timing parameters unique to the corresponding sounder device, the one or more timing parameters specifying when an audible alarm is to be emitted by the corresponding sounder device. A broadcast alarm message is sent to all sounder devices. In response to receiving the broadcast alarm message, each of the sounder devices emit an audible alarm in accordance with the one or more timing parameters unique to the corresponding sounder device relative to a time of reception of the broadcast alarm message to produce the perceivable sequential audible sweep from the sounder devices toward the exit of the facility.