If a site is large or particularly hazardous; or where employees are at higher risk, the ability to instantly know the location of an incident saves vital response time. Depending on the Ascom application used there are several means of establishing where the alarm originated.

Caller ID

This is the simplest method in which each handset is programmed with a unique identity code. It is only suitable in situations where staff always work in the same area and do not move around the site. When an alarm is triggered, the ID code is transmitted and can be matched to the known location.

Infra Red Location

This uses a series of small infra red transmitters placed at key points around the site. Each continually emits ‘address’ information, which is stored by the pocket unit as staff move around. When the wearer raises an alarm, the unit automatically transmits the last two ‘addresses’, along with the type of alarm. This can be sent to a central control, other handset carriers, or a remote off site connection. Location data is displayed on a site map stored on a PC, or texted to individuals or specific groups of handset carriers. The alarm can also concurrently trigger third party safety and security equipment. Data can include the type of alarm, man down, no movement etc.. Plus there are options for sending an automatic acknowledgement to the person in distress that the alarm has been received.

Low Frequency Location

This operates in the same way as the Infra Red system, except it uses a low frequency magnetic field to send ‘address’ information to pocket units. LF locators are appropriate where areas outside buildings need coverage in daylight, or where staff need to wear their pocket alarms under clothing. Because there will always be some installations where both location methods have a role, some pocket alarms combine both IR and LF in the same handset.

Base Station Location

If IP-DECT or DECT handsets are used, the alarm message automatically includes the person’s identity and approximate location, derived using the reference code of the originating base station. Alarm messages will override other traffic even if handsets are currently engaged in a speech call, or in mute mode.

DECT Location

With the same functionality as IR Location, DECT Location offers higher accuracy and reliability. Instead of using base stations, twin antennas are used to provide location information. They can be more discreetly placed, for example inside and behind walls, in ceilings etc., they can also be tamper protected.