ChildAlert is part of the Safe Guard suite of software products specifically designed to improve the security and safety of Nurseries. It uses advanced, 'active RFID' technology to warn staff that a child may have wandered outside the nursery premises.

RFID Tags explained

Probably without being aware of it, we have all had experience of RFID (Radio Frequency Identification) tags. They are an accepted part of everyday life and are to be found in many shops, usually attached to the merchandise. When passed through an RF field, the tags become energised and send out a digital code to be picked up by the aerial at the exit door. These tags are known as 'passive RFID'. They have no power source and rely on the RF field to provide a very small amount of energy for them to operate. The drawback to this technology is the limited range - usually no more than a metre or so.

ChildAlert uses 'active RFID' tags. These are fitted with a small battery inside and emit a unique digital code when they are moved. They are sealed units and the batteries, which are similar to those found in a hearing aid, have a life of approximately 5 years. These tags are child proof and completely harmless.

ChildAlert - The Principles

A tag is provided and allocated to each child. These are about the size of a credit card and are normally sown into the back of a tabard or slip over vest, which is worn by the child.

An RFID reader is placed somewhere convenient in a central location - often in the loft or the roof space. This reader has an aerial. Depending on the local situation, this aerial may be a small omni-directional whip about 150mm long. In this instance the reader could be mounted on one of the internal walls. The useful range of this is about 20 metres, but is reduced when going through walls. Alternatively, a high gain aerial may be fitted which is a flat plate about 300mm square. This has a 'line of sight' range of around 50-60 metres and is cardioid shaped. Any number of readers can be employed with the software to ensure maximum coverage. The readers are connected to the nursery's computer network via a small interface box.