Baby monitor

It transmits the sounds by radio waves to a receiver unit with a speaker carried by, or near to, the person caring for the infant.

Baby monitors continue to evolve and now also can utilize features such as night lights and built-in lullabies.

Some include temperature and movement monitoring devices to sit underneath a mattress or close to the baby within a cot.

Digital audio wireless systems using DECT, are resistant to interference and have a range up to 300 m.[3] Analog audio transmissions can be picked up at a distance from the home by a scanner receiver or other baby monitor receivers, and so present a risk to privacy as long as the transmitter is switched on.

FM transmitters, paired with a microphone can be an inexpensive solution to a DIY baby monitor, since clock radios can also be used as one.

This is often in the form of a set of lights to indicate the noise level, allowing the device to be used when it is inappropriate or impractical for the receiver to play the sound.

Transmitters with movement sensors such as a pressure-sensitive mat placed beneath the child's mattress give additional warning of restless activity by the infant.

The new voluntary ASTM International F2951 standard has been developed to address incidents associated with strangulations that can result from infant entanglement in the cords of baby monitors.

It provides requirements for labeling, instructional material and packaging and is intended to minimize injuries to children resulting from normal use and reasonably foreseeable misuse or abuse of baby monitors.