A literature survey was conducted to study the available research connected to wakening of sleeping people from the sound of a smoke alarm. The effect on the sound attenuation from typical building materials has also been studied.

While the common high frequency signal used in residential smoke alarms will wake up most unimpaired adults, is not the most efficient alarm type to awaken certain groups of the population. Children, elderly and people influenced by alcohol or medicines that affect sleep belong to the group at risk of not being awaken by the sound of the common smoke alarm.

A 520 Hz alarm signal have been shown to efficiently wake up the general population as well as people at risk. This signal has also been shown to maintain its sound level more efficiently when transmitted through and via ordinary building components in dwellings.

For this reason, it is recommended that product documentation related to the CE-marked smoke alarm should include both minimum sound output (dB(A)) as well as describing the tone (e.g. frequency) in order for the consumer to be able to make an informed choice that fits their needs.