Personal Alarm System for Emergency Response

PAS is an ultrasonic emergency notification/communication system. The location of an individual moving throughout a facility is immediately determined when he or she activates their Personal Alarm Transmitter (PAT) device. Through integration with an overall security management system, the location of the individual requiring assistance can be graphically represented on a map-type display at a central location.

Icon of sound frequencies representing the ultrasonic technology of PAS

Ultrasonic Signal Technology

  • Ensures reception of alarm signal
  • Results in very few false alarms
  • No “bleeding” of signal between walls or floors
  • Variable range to 30 m (100 ft) diameter

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Immediate Detection and Location

  • Accurate location identification
  • Timely response to an individual in distress
  • Audio output for assessment purpose

Icon of a finger pressing a button, representing flexible activation options

Flexible Activation Options

  • Push button activated
  • Pull pin activated
  • Pull ring activated
  • Man-down option available

How It Works

One or more receivers are installed in each room or hallway that the system is required to cover. Upon activation, the transmitter carried by an individual emits a continuous ultrasonic signal. Receivers will only alarm when they receive a transmission containing specific frequencies in an established pattern. This eliminates false alarms from items such as keys, metallic items, and HVAC systems. The signal is omni-directional, eliminating the need to point or direct the transmission.

PAS personal alarm system components - belt worn transmitters and wall-mounted receivers

PAS Features


PAS transmitters are discreet, compact and rugged and can be worn on the belt either with a belt clip or in a holster, or as a pendant. Transmitters can be activated by button press, pull-pin, pendant pull-ring or self-activated in a man-down situation. Receivers are flush-mounted in the wall or ceiling and provide an alarm output, auxiliary alarm output and a visible LED that illuminates when an alarm is received.

PAS Receivers

The PAS receiver decodes the modulated ultrasonic signal emitted by the PAT. An alarm contact, auxiliary contact and LED activate each time an alarm is received and remain latched when an activated transmitter is within range. Receiving range is factory adjusted for a nominal distance of 15 m (50 ft) radial, 30 m (100 ft) diameter and can be field-adjusted as required.

PAS Transmitters

The PAT is activated by pushing a latching alarm button which has been specifically designed to prevent accidental activation. Additional methods are available as options, including pendant pull ring, pull-pin and “man down” (“man down” provides automatic transmission whenever an individual is in a prone position for a period of time). A breakaway lanyard is supplied with the PAT/C (compact unit) while sturdy pocket/belt clips enable a variety of carrying positions.

PAT Test Unit

The PAT test unit allows customers to regularly test the PAT units and maintain confidence in the operation of the system.

Additional Resources